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Divergence in preferences are real! My preferences are weird. You probably wouldn't have liked them. Look at the design goals in the early versions of the manual or even later versions. If I'd stayed in charge (or even asserted a more robust sense of "being in charge" when I was nominally moreso) the result would have been, I think, fairly unpopular. The Rust I Wanted probably had no future, or at least not one anywhere near as good as The Rust We Got. The fact that there was any path that achieved the level of success the language has seen so far is frankly miraculous. Don't jinx it by imagining I would have done any better!

Play for 57 hours

To put into perspective how fast levelling is in D4 compared to D2R, the first level 99 on Diablo 2 Resurrected was achieved by a team of players who took turns levelling up while the others slept. Nonstop grinding until they collectively got level 99 after 7 and a half days of nonstop grinding. This is after the fact that we know exactly the most optimal way of earning experience. In D4 we will eventually find even faster ways to level up.

Ladder Season 1 in Diablo 2 Resurrected began on April 28, 2022. In a massive team and community effort, the first Character "Teo_Unsullied", played by Teo1904, reached Level 99 with a Lightning Fury Amazon. This feat only took 7 days and 10 hours!

Donc 20 ans après sa sortie, alors que les mécanismes sont connus par cœur, le leveling de diablo 2 prend encore 3 fois plus longtemps que celui de d4, qui vient pourtant à peine de sortir…

L'histoire de comment la guerre intestine entre l'armée et différentes administration américaines a abouti à contourner puis lever les limitations appliquer artificiellement aux GPS à usage civil.

I want to augment this answer to address the end of Selective Availability (SA), which drastically increased the utility of GPS.

First let's talk about SA:

When they first provided 'free to all' GPS, the AirForce created Selective Availability - a scrambling code on the C/A signal that made it worse than it normally would be (by about 10x). This made C/A GPS 'good enough to navigate off of' but not good enough for military application, as the US was worried about adversaries using it.

Specifically, SA worked by introducing deliberate errors into the time signal sent by the satellite and providing incomplete information about the satellite's position. This was done because without it C/A would have been too precise for the military's comfort--it was arguably more accurate than had been intended. In the 1980s, civilian receivers just using C/A had been able to get approximately 20m accuracy in horizontal position. SA, implemented in March 1990, made that more like 100m. You could stand in a field with a civilian GPS receiver and watch your position bounce around--more on this later.

So under the SA regime, GPS could not be used for some of the precise navigation tasks we now take for granted. My favorite example of this is that the hobby of geocaching is an entirely post-SA phenomenon, with the first geocachers being attested just after SA was turned off in the first seconds of May 2, 2000. In addition, car navigation was pretty terrible under SA: getting within 100m of a particular address might be acceptable, but the stupid GPS not knowing if you're on this road or some parallel road makes it useless. You simply couldn't conduct street-level navigation. And of more significance, both commercial aviation and maritime shipping didn't find SA-corrupted GPS sufficiently precise so had to continue to use other navigation systems that cost a lot to maintain. This was frustrating for stakeholders in those industries including the government agencies that promoted, facilitated, and regulated them.

So here's the end of SA:
In 2000, the US formally turned off Selective Availability, allowing civil use (I am omitting the reasoning I have always heard for this because I cannot cite a source).

Officially, President Clinton claimed the benefits of zeroing out SA and allowing everyone to use accurate signals were great while there would be "minimal impact on national security."

What I've heard may or may not be what other people such as u/Conrolder heard: basically, SA was in the process of being defeated by technologies that were being not just developed but actually fielded by the Department of Defense's adversaries in . . . other agencies of the federal government. (You thought it would be the Russians.) And I'll point to the National Academy of Sciences' (NAS) 1995 report The Global Positioning System: A Shared National Asset (download) as a source for this though I'll admit that was not the way I first became aware of this issue.

Remember that guy standing still in a field in the mid-90s watching his position bounce around? Advocates for civilian use of GPS had been doing similar experiments since the inception of GPS and realized that some of the errors in position are systematic. The could be corrected in real-time if you had a ground station send information about the discrepancy between its fluctuating GPS-indicated position and unchanging actual position. SA-introduced errors were very similar for users who were close to each other and relying on the same satellites.

The basic concept of correcting GPS based on fixed ground stations is called Differential GPS (DGPS). DGPS was actually being implemented by U.S. government agencies in the 1990s. Most notably:

The U.S. Coast Guard (USCG) created a system simply called DGPS that broadcast correction signals on marine longwave frequencies, prioritizing maritime users. DGPS was generally available to maritime users who had compatible units starting in 1994; prior to that, USCG and several other agencies (including the U.S. Army Corps of Engineers, National Oceanographic and Atmospheric Administration, and National Air and Space Administration) had been using DGPS for internal purposes such as precise siting of navigational and surveying aids, cartography, and scientific research.
The FAA and U.S. Department of Transportation (USDOT) was aiming for a more ambitious system known as Wide Area Augmentation System (WAAS). The DGPS system from the ground stations would be relayed to satellites over the United States, who would send it back down to primarily aviation users in the same frequency band as GPS. WAAS wasn't operational till 2003 but it was already under discussion in the 1990s.

These systems actually improved the positions that could be derived from the C/A to better than had been available in the pre-SA days, by not just rendering SA a non-factor but also counteracting some of the environmentally-induced imprecisions. There are actually a bunch more DGPS and other GPS enhancements. Your smartphone probably uses some of them, but I'll leave that aside for now. Note USCG DGPS was discontinued in 2020 because it was redundant to WAAS.

If you read the NAS report I referenced, it contains strong recommendations that SA be discontinued in part because the various DGPS systems had or would soon render it obsolete. The war between SA and DGPS was being waged by the U.S. government on both sides. But there was no reason other actors couldn't also come up with their own DGPS systems. And--again--GPS had substantial potential that SA was blocking. I'd go so far as to say you probably wouldn't have GPS in your smartphone if SA were still running and DGPS had somehow been banned.

Le commentaire initial sur l'histoire du GPS était intéressante aussi :

I'm a GPS engineer. I'll answer this in a sort of roundabout way by explaining the history of GPS and how it works - then get into why it's used for civil application and why you don't have to pay for it.

GPS was originally a US AirForce program called Navstar. Navstar started in 1973. It was a spiritual follower of other navigation-based programs such as Loran (a 2D positioning system for ships on water), and Decca (a hyperbolic radio navigator based on calculating one's position based on the intersection time of radio signals). These hyperbolic navigation systems were originally started in WW2 to assist bomber runs.

The idea of a space-based version of a navigation system is said to have started with the Soviet launch of Sputnik-1. A group of DoD funded engineers at APL were tasked with figuring out where Sputnik-1 was, and because Sputnik-1 transmitted a continuous waveform, it experienced a measurable doppler shift (if it traveled towards you, it sounded higher pitched - when it passed overhead and continued on, it had a lower pitch). In this way, a group of scientists at APL were able to figure out where Sputnik-1 was! [1]

The US DoD then began to investigate new methods for navigating off of radio signals from space specifically, eventually leading to Navstar. Navstar as a program was born near the end of Vietnam. During Vietnam, if the US wanted to destroy a bridge, they had to fly sorties over that bridge and drop bombs in the hope that one of those bombs would hit. They had a very high miss rate, caused immense collateral damage, and costed a lot of money because the accuracy of bomb drops was so low (I won't pull a reference for this, but the Thanh Hóa bridge is a great example of this problem). Thus, the Navstar program which would become GPS was implemented to try to resolve the massive challenges associated with target accuracy and navigation.

The Navstar program spent 25 years getting from program inception to final delivery of a full GPS constellation (you need around 30 to navigate, because they're medium-earth orbit globally orbiting satellites, and you need four overhead at any given time to work - it took them a while to get all of those up!) GPS works by resolving the GPS pseudorange equation through trilateration. That is, the satellites transmit two things (broadly): 1) their own precise position, monitored by a group of surveilled ground control monitoring stations around the world, and 2) the precise atomic reference time at which their signals are transmitted using on-board clocks occasionally updated/corrected from the ground. A receiver on the ground has a bad clock and doesn't know where it is, so it resolves a nonlinear equation with four unknowns (it's position in 3 dimensions and its clock error) from the GPS satellites. It's hard to explain without getting into the math, but just know that in this way, all GPS receivers receive very precise timing, as well as their position, by calculating the intersection of four spheres (a great depiction of this is here: https://ciechanow.ski/gps/).

During the Navstar program, there was a big push for GPS to be provided as a civil service. For starters, it gave near-atomic clock quality time for next to nothing in cost (you get the benefit of the GPS satellite clocks on your handheld receiver), as well as instantaneous position globally. The timing in particular was a really big deal to the US here - the power grid requires precise timing, the stock market does, etc. The GPS program made all of those things cheaper, better, and easier. So the DoD was always considering some version of a civil service for GPS. And then in September, 1983, Korean Airlines Flight 007 accidentally flew through restricted soviet airspace and was shot down, killing 269 people. This was the final incentive that the US needed to publicly provide a GPS civil service.

Another reason that the civil service was allowed was technological. The GPS satellites, which were AirForce assets, transmit a signal called P(Y)-code, which is a military GPS signal with an encrypted code (only military receivers can use it). At the inception of GPS, it could not be directly acquired (doing so required that you knew pretty well where you are), so the Navstar team developed something called "Coarse Acquisition", which was another, worse signal that could be navigated off of in order to get 'good enough navigation' to get to P(Y)-code. This signal was already being transmitted for military use, and by providing it for civil use, civilian users got a worse version of GPS through C/A. In other words, providing civil use didn't negatively interfere with military use, made stock market and power grid work cheaper (and many other things like public infrastructure development, surveying, etc.).

When they first provided 'free to all' GPS, the AirForce created Selective Availability - a scrambling code on the C/A signal that made it worse than it normally would be (by about 10x). This made C/A GPS 'good enough to navigate off of' but not good enough for military application, as the US was worried about adversaries using it.

In 2000, the US formally turned off Selective Availability, allowing civil use (/u/abbot_x gives a great answer as to why in the comments below). Today, the GPS program is one of the only military programs where civil services (the Department of Transportation, I believe) sits on the stakeholder committee for the branch that runs it out of AFRL, and they use it for everything. And a lot of other countries have navigation satellite constellations too now (the EU, Russia, China, Japan, and India).

TL;DR: US taxes paid for GPS, but you really get access to it because it helps the US government substantially in aviation, civil, infrastructure, economic, and military sectors, and the version of GPS that you're using is still substantially worse than the one the military uses. There's some legacy effect here too - the US originally only let civil users use an acquisition code that was never meant for navigation, whereas now they have dedicated civil use signals (mostly due to the intense peer pressure of continued civil reliance).
[…]
Also a good online resource for all things GPS is Navipedia, produced by the European Space Agency but broadly maintained as a wiki (if you want to take a look at more of the math).

First, (and I've fixed the post above with this), the GPS trilateration equation is nonlinear, and you can see a great visual of it here: https://ciechanow.ski/gps/ (somebody posted this and it's very cool and I think their comment got deleted).

Second, I commented on some major differences between the different constellations here: https://www.reddit.com/r/bestof/comments/13ypf9i/comment/jmql9g2/?utm_source=share&utm_medium=web2x&context=3.

Third, there are a lot of comments regarding time dilation. Fun history fact - the first space-based precursor to GPS was called Transit, and was the first technology that had to actively account for time dilation or stop working, and it assisted in proving Einstein's Theory of Relativity (or perhaps more aptly, continued to prove it). GPS does the same thing! Today it still accounts for time dilation through regular updates to the timing on-board satellites.

Fourth, just as a note to really try to hammer home WHY GPS is free, GPS is estimated to produce $1.4 trillion per year in economic gains for private-sector businesses (https://www.nist.gov/news-events/news/2019/10/economic-benefits-global-positioning-system-us-private-sector-study). This is in addition to all of the governmental gains in infrastructure, transportation, aviation, power grids, stock markets, good ol' timing, etc. I think part of the trick here is that the US knew this would have impact that extended way beyond the already massive military application, and events like Korean Airlines 007 were a straw that broke the camel's back on that discussion. But making it 'free' already saves the US a ton of money (both for private and public use) and that more than any other reason is why it's free!