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Valve runs its massive PC gaming ecosystem with only about 350 employees
(arstechnica.com)
This is a most excellent place for technology news and articles.
Since 2012:
That's just what I remember off the top of my head. I'm sure there's more that I just don't care about.
Remote Play Together is another big one for many, I've used it together with Retroarch, so much fun.
Oh yeah, and I didn't mention Steam Family sharing or whatever it's called now. And Steam Link.
Proton and Steam Input are biggest. And while Proton is built on shoulders of giants(wine), Steam Input is something that didn't exist.
Hell i use steam for proton and linux. It really makes gaming so much easier than other services