"Proton to bring Windows-only games to Linux, " - wine for instance? I am not actually a linux user as such but even I know steam aren't going to be a hero on that platform once they have their claws in. I mean, just look at how they take a free linux platform and then budle it with their proprietary client to ensure they have you trapped in for data mining, monopoly etc.
https://store.steampowered.com/steamos/
"Remote Play to play PC games on TVs and mobile devices" - mmm, should I play in a slouched back breaking sofa position playing my game on a substandard lower resolution monitor, whilst trying to balance keyboard and mouse on my knee whilst getting RSI. Nope, think I will sit at my hugely powerful desktop running ultrawide 3440*1440 at 100 fps+
"Remote Play Together with only the host required to own the game to play local multiplayer with friends remotely and cross-platform, " - I never play multiplayer so can't comment on this but does this not depend on the game specifically. If a game can be played LAN then why bother with all that.
"the rumored Steam Cloud Gaming to play on low-end machines. " - yay, more streaming!! Thankfully the net is 100% fully on all the time guarenteed with no dropouts, lags etc. and steam will never switch off my access to it. Personally I think this is a knee jerk reaction to stadia and will likely fail.
So to summarise:
"steams play anywhere" - so long as you are allowed to by steam, have full fast internet connectivity, and don't mind them auto patch breaking your software, then its probably a great idea.
"gogs drm free" - its mine, brought, downloaded using any old browser, saved on my offline backups, fully playable any time, fully under my control.
As always, rent or buy.