From the opinion piece:
Last year, I pointed out how many big publishers came crawlin’ back to Steam after trying their own things: EA, Activision, Microsoft. This year, for the first time ever, two Blizzard games released on Steam: Overwatch and Diablo 4.
Again steam did not do this to drive game sales, otherwise they’d have done this before they needed a deck solution.
Proton exists far longer than Steam Deck. You don’t know what you’re talking about.
And steam has been trying to push linux based steam hardware before proton, so maybe you are out of your depth here?