As Steam keeps breaking things for Linux(all for their stupid chromium UI overhaul) its been really hard to use VR unfortunatly.
Last resort: Try uninstalling steam and delete all steam related files(except the folder with all you downloaded games), delete all Steam and VR related files in .config and .local. This is as much of a fresh start as you can get and it should work. Use latest ALVR nightly.
I just hope nothing “extra” gets tacked on…