The main advantages of Bazzite versus SteamOS is receiving system packages in updates at a much faster rate, choice of an alternative desktop environment, Waydroid support, layering system-level packages at your own risk without messing with the filesystem, and printing support.
From their FAQ page https://docs.bazzite.gg/General/FAQ/
Pretty much all linux distros have printing support
Except SteamOS, as I discovered when I needed it badly.
Still, I’m sticking to SteamOS on the deck and Bazzite for the desktop.