Bazzite is one of the best options to get Linux on various gaming handhelds, and the 3.5.0 release is out now that has improvements pretty much everywhere with expanded hardware support.
Bazzite is a cool alternative to SteamOS, but it's only had partial support for the OLED Deck. Thankfully that seems to be fixed in the new release.
I might switch back to Bazzite when it hits 4.0. I had used it on OLED since 2.4.0, and while it definitely worked, constant audio issues, Bluetooth issues, and very slightly worse power consumption didn't justify the switch.
If you use your Deck as a docked laptop, though, it might be worth it. The fact that system updates don't wipe out your layered apps and settings is huge, if that's what you need.
I run it on a laptop being used as an HTPC, and it's been great for that!