The benefit to/for Steam itself is marginal. The benefit to the entire community is significant, because there's now an entire metric shitload of obsolete 32-bit shit that can be safely deleted and forgotten for 95% of the Linux world and efforts can be focused on things that actually matter in the 64-bit world. The entire 32-bit ecosystem of libraries and system layers still had to be maintained and supported basically only for Steam's sake, Steam was the only thing still using them for the vast majority of people. It's not that Steam needs 64-bit, it's that 64-bit is the standard now and has been for a long time, and Steam was the only thing that had no 64-bit version.

It's kind of like cutting loose the anchor that the community has been dragging around everywhere for years for no purpose. It was a totally unnecessary effort that just caused suffering and added no value.

Started writing a lengthy response, then came across this Wikipedia link which slamdunks it: https://en.wikipedia.org/wiki/64-bit_computing#Pros_and_cons 😅

One of the benefits is only needing to have 64 bit libraries. With this change most people can drop their 32 bit stuff.

Bits are literally "binary digits". So more bits means bigger numbers. The reason you get more memory, is because when the code says "put this data in memory spot (number bigger than 32 bits)" .. you cant with only 32 bits. How do you represent that number.

Imagine that you want to put something in memory spot 150, but you only have 2 digits. You cant. Bumping it up to 4 digits, you can say "put this data in memory address 0150" and its fine. "bigger numbers == more addresses == more places to put stuff"

So anywhere you need a number bigger than 32 bit represents, you can either just use a 64 bit number, or do a bunch of shenanigans. Those shenanigans require extra calculations inevitably. https://en.wikipedia.org/wiki/2,147,483,647 If youve ever seen this number before, it's probably because of a 32 bit limitation. It shows up all sorts of weird ways.

Bigger numbers here aren't about taking up more space, just representing literally bigger numbers. "9999" only takes up 2x as much "space" as "99" but it repesents a number ~100x bigger.

Sorry, I'm tired and rambling.

One of the reasons Steam held out for so long was that a lot of the games they host are 32-bit only. Games are built by a company, many of which have gone belly-up, so rebuilding the game from scratch is impossible. Making Steam 32 bit even though it could be 64 bit is a really effective way to guarantee a large chunk of their legacy products will still run. In a lot of ways, because of the nature of the gaming industry, Steam has it worse than most package managers/app stores.