I don't think it's currently possible for any cloud service to make this obsolete, at least in the ways that I'd want to use a portable gaming device. Which is to say, mostly in transit, which tends to have spotty (at best) internet accessibility. (In the air on an airplane, between stops on the subway, ...)

Tried Stadia. Wouldn’t ever let me start a game no matter what I tried.

Ended up giving up after two months and went back to either GeForce Now or my Windows partition, depending on the game.