It is a copy of SteamOS which uses its own Wayland compositor (Gamescope) that is not compatible with anything other than AMD (since it was originally intended to only be used with Steam Deck, there was no reason to make it work anywhere else)
I would have thought that installation of Nvidia driver packages for Arch would do the trick. I'll admit that I'm unfamiliar with the interaction between GPU drivers and Wayland, so I'm guessing it would just result in an unstable combination?
Not just unstable, until I think 2 years ago literally not useable as the nvidia proprietary drivers didn't implement useable GBM by default, so even if it didn't hard crash it would never show anything besides a blank screen.
