Desktop mode on the Steam Deck uses X11. I think that's why the brightness control is fucked up (ever notice how the brightness is always 40% when you switch to desktop mode?). You can manually switch it to Wayland, but Steam input is broken under Wayland (or at least it was last time I checked, which is admittedly half a year ago or something).

> input is broken under Wayland

Drop the ‘Steam’, it's cleaner. Wayland's raison d'etre is to push frame buffers without tearing. Input is an afterthought.

> Input is an afterthought

This. You need more than graphics to have a windowing system. Wayland team threw out X11, did graphics and left the rest for the others to figure out.

That's odd, I'm using Wayland on my desktop and, for example, Japanese input works 問題ない. Then again, I haven't tried every possible input method/peripheral in existence, so I may just be the one in [some arbitrary large number] who lucked out.