I have been running Bazzite on my TV for a few weeks. Was using PopOs however I was having issues with some games not launching, probably to do with the combination of Unraid VM, GPU passthrough, Xorg with fractional scaling on a 4k pannel. Bazzite with "Game mode" is amazing. Closest thing to Steam OS that I know about. Everything just worked with the exception of needing to firmware update my xbox controller to get it to work. Game mode seems to report as a steam deck.
Highjacking your comment to mention the 8bitdo Ultimate 2C, for anyone looking for a 8bitdo controller
Haven't personally tried it yet, but LTT made a video about it and price, quality and features seem all pretty good.
https://www.youtube.com/watch?v=3N5MlZg_Cdg
I also haven't used the 2c, but the older bt+usb2.4 ultimate still can't be configured in linux and the android app seems to not work at all.
I like the 8bdo controllers but being able to remap and set deadzones would be nice, and I'm waiting for steam controller 2 at this point. hopefully they do hall sticks.