You could play games from any generation, at the right settings, with the right mods. Despite Xbox’s great Backwards Compatibility efforts, games like GTA IV run at 720p on XSX, or games like RDR2 still run at 30fps. I really want to play Kingdom Come Deliverance but sadly it is locked at 31fps consoles, while it can run at 90 on Rog Ally, despite being much weaker machine. There are PC mods that make the games combat system much better, that will never run on consoles.
You could emulate games freely without having to worry about sandboxed systems like XSX/PS5 or waiting for a remaster. Case in point; MGS Master collection.
You would get cheaper prices as Steam allows you to have multiple store fronts, which would lead to better competition. They don’t care if you run EA launcher or Ubisoft launcher or never buy a steam game on a SteamDeck. They know they’re that good that you’ll come to Steam no matter what.
You could play so many more games that never launch on consoles.
It would still be a PC, which, if you really wanted, could be used for whatever purpose you like, preventing it from becoming ewaste like these digital only consoles might end up becoming if and when servers close down.
It will be better like so;