Valve is in a funny position now. They lived long enough to see every one of Sony and XBOX's moats dry up by being pro-consumer where possible, but with Steam as the leader of a fungible game distribution market it may no longer make good business sense to continue to act so benevolently.
We've reached a sort of gaming singularity where nearly every video game can be run on any hardware you choose or be streamed over the network to a thin client. PlayStation and XBOX consoles are basically dedicated gaming PCs that can only run Sony or Microsoft's version of Steam. DirectX is losing ground too thanks to Proton and Vulkan, so Microsoft won't have the last laugh there either. If Valve controls the store you purchase games from, the software which runs the games, and the operating system running the software, they are an ODM contract away from becoming Sony's PlayStation division, and look where they are now.
> DirectX is losing ground too thanks to Proton and Vulkan
[citation needed]
My understanding is that Proton is effectively a distribution of WINE + DXVK, which does for DirectX what WINE does for Win32. Valve is even on record saying "make one good copy of your game and trust our compatibility tools to port to other platforms" which is effectively saying "use DirectX if you want - Proton will run it just as well."
Steam still has to deal with Epic being willing to throw billions at trying to dethrone Steam, and Gog being alive and well and being in the perfect position to say "we told you all along that you shouldn't have to trust Steam, buy your DRM free games here". Also every big publisher wanting to pull their own games to their own storefront and only being forced to crawl back because gamers refuse to leave Steam
And even if they somehow arrived in a market position where being less benevolent would make more money: Valve isn't publicly traded, nobody is forcing them to make the most profitable move. As long as Gabe and the other owners prefer being benevolent they can continue doing it
(not that they are all around benevolent. "consistent" and "usually choosing the side of the customer over the side of the publisher" is maybe the better framing)
One point in Steam's favor (not to suggest that Valve is above reproach) is that it doesn't impose any DRM. If games have DRM, that's the publisher's decision.