Strictly speaking the mobile Oculus/Meta Go/Quest headsets were linux/android based, you can run Termux terminal with Fedora/Ubuntu on them and use an Android V

Strictly speaking the mobile Oculus/Meta Go/Quest headsets were linux/android based, you can run Termux terminal with Fedora/Ubuntu on them and use an Android VNC/X app to run the 2D graphical part. But I share your SteamOS enthousiasm.