man I remember using a 8" windows tablet with a 3d printed mount to a xbox controller to be able to play steam games like hyperlight drifter, it was so cool at the time but man did it suck holding it for long and the performance was so bad for anything but the simplest game. after that I turned to steam link with my phone and a razer kishi controller, I setup a headless steam docker on my server to keep my games accessible and that worked pretty well when 5G came out but nothing really beats games running on the hardware you hold in your hand, at least not for a good while