A lot of older PC games can run just fine on modern phone hardware. I’d buy a SteamOS version of a phone that has some modular or built-in set of buttons and analog sticks. I don’t know how the app ecosystem would work for sensitive things like banking but it’s mostly a minor issue for me.
As an alternative for the Apple/Google duopoly, I’d be curious. As a gaming machine, having tried playing PC games on Android, I’d say a lot of work is still needed.