The games I pre-bought to play on Deck, these aren't the games I play on it. I figured it would be good with things like Days Gone, Citizen Sleeper, Disco Elysium, but instead I ended up playing mostly Euro Truck Simulator 2 in the early days. The driving is surprisingly good handheld, far superior than keys and mouse.
Yeah. When I bought mine I got a bunch of platformers, roguelikes, etc, and loaded them on. I put Tekken 7 on there as a stress test and it's probably the thing I play the most.