My best guess is that you have an GPU that either doesn’t support Vulkan, or has driver issues. But we shouldn’t guess, that’s what logs are for.

For Steam logs, running Steam from terminal as suggested is one way. Do note that error with wrong ELF class for game overlay library when starting any game is normal, since Steam tries to load both 32 and 64 for bit version for each game, and the wrong one will always fail. Arch wiki has more information.

https://wiki.archlinux.org/title/Steam/Troubleshooting#Debugging_Steam

For Proton logs, set environment variable PROTON_LOG=1. You can do it in Steam launch options, see Proton Readme for more info.

https://github.com/ValveSoftware/Proton?tab=readme-ov-file#runtime-config-options

With hardware and firmware issues system logs often point to right direction. Again Arch wiki has a good tutorial on it.

https://wiki.archlinux.org/title/Systemd/Journal#Filtering_output

Games often have their own logging too if you need to go there. You’ll need to look those up, as they vary by game.

I hope this helps.

First, make sure you are using EXT4 file system on your drive, and it’s on /etc/fstab. Then you could see if mounting your HDD to your main steam library location on your home dir fixes the issue.

It’s always a good idea to check steam logs to get a better idea what could be going on.

The issue tracker is here: https://github.com/ValveSoftware/steam-for-linux/issues

If you filter issues with keywords “external library”, you have 68 open issues to compare to yours. Eg. one is a shader pre-cache issue, disabling shader pre-cache may help. In another one people report needing to run a console command to mount the external library.

Hope this helps.

I used to run Steam BPM under steamcompmgr, and had Kodi as a shortcut via “add a non steam game”. You could do a browser similiar way. steamcomomgr is a X window manager that handles scaling for those small dialogs for TV screen. Gamescope is similiar for Wayland.

Now I have Debian stable running plasma-bigpicture, which is a KDE set up for TV screen. Flatpak gives the latest Kodi and other apps that the OS doesn’t keep up to latest version, and I do enjoy the stability of the underlaying OS for HTPC use.

Which is better? It depends. If you do mostly games and Kodi, and use a game controller for controll, then Steam BPM. It has a controller friendly OSD keyboard for text, and the upscaling of starting dialogs especially for older games if a nice feature. For youtube, this may not be the best option, and it needs a bit more work to set this up for the Display manager as a xsession.

Plasma-bigpicture is nice if you want to run apps made for traditional desktop, and have a keyboard and mouse. Say for youtube you may want to use some unofficial players to get rid of ads. You can set Steam to auto-start on the background to get game controller input working on the desktop. Setting this up is as easy as installing one package, and switching the session via login manager.

Ofcourse, you can have both and switch from you login screen. You can’t have Steam running on the login screen for that game controller friendly keyboard for login, but you can set automatic login for the one you use most, and switch by logging out.

As for distro, pick the one you like most and know your way around.

I hope this helps, have fun.