Valve is a Linux and Arch MVP, and as a die-hard Linux user, my appreciation for them is immense. Without Valve's efforts, Linux user base would be a lot smaller because a lot of people would be using Windows. I wouldn't be able to game (since I am a Linux-only house) without a complicated windows VM setup. So just the fact that they support Linux with their proprietary software, and the fact that they used Arch for the Steam Deck (giving strong commercial incentive to game devs to support linux or at least proton, which IMHO is good enough) is a big contribution to the community. They also made the Steam Deck fully hackable by the owners, so you can do neat things with it including running all your games from some other store if you want.
But on top of that, they contribute a ton of things that benefit even people who never touch Steam. Valve slings graphics stack and GPU code, and of course Proton/Wine, Gamescope, and a handful of other things. They are awesome about upstreaming stuff, and when it's not upstreamable (say for example a new or standalone project) they tend to open it.
Proton, Gamescope, Linux ESync/FSync Patches are all at least related to valves efforts from what I can gather and as an Arch User I feel it's the premier linux gaming distro due to valves efforts.
I think most of the work Valve does is upstream from Arch though but it's trickling down very fast (with arch, sometimes hours, if it's an AUR-Git package, seconds).
PS: The core of Valve's technical contribution is around the SteamDeck. You already know it runs Linux, Proton, yadayadayada. An obvious fact that only clicked for me after being mentioned in the presentation: if you aren't in the Steam store but want your app on the SteamDeck the primary option is a Linux version (distributed through flatpack). That (commercial) incentive alone is a huge benefit. Suddenly you can make a business case why your product maybe should support Linux.
¨Apart from sanitation, the medicine, education, wine, public order, roads, the fresh water system, and public health ... what have the Romans ever done for us?"
> I feel it's the premier linux gaming distro due to valves efforts.
For anyone reading this: virtually every piece of code is upstreamed to the projects themselves (Mesa etc.), there is no reason to jump to Arch for gaming.
But on top of that, they contribute a ton of things that benefit even people who never touch Steam. Valve slings graphics stack and GPU code, and of course Proton/Wine, Gamescope, and a handful of other things. They are awesome about upstreaming stuff, and when it's not upstreamable (say for example a new or standalone project) they tend to open it.