Trying to launch any of my games via Proton just shows the "preparing to launch" message before immediately going back to the green play button. Even with PROTON_LOG=1 %command% in the launch options, no log is generated in my home folder, but opening Steam in the terminal and trying to launch a game gives this:
chdir "/var/home/[REDACTED]/.local/share/Steam/steamapps/common/Dishonored/Binaries"
ERROR: ld.so: object '/var/home/hanlonmj/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
ERROR: ld.so: object '/var/home/hanlonmj/.local/share/Steam/ubuntu12_64/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS64): ignored.
ERROR: ld.so: object '/var/home/hanlonmj/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
Adding process 15059 for gameID 205100
Adding process 15060 for gameID 205100
WARNING: discarding _NET_WM_PID 5 as invalid for X11 window - use specialized XCB_X11_TO_PID function!
WARNING: discarding _NET_WM_PID 5 as invalid for X11 window - use specialized XCB_X11_TO_PID function!
Uploaded AppInterfaceStats to Steam
Removing process 15060 for gameID 205100
Removing process 15059 for gameID 205100
WARNING: discarding _NET_WM_PID 5 as invalid for X11 window - use specialized XCB_X11_TO_PID function!
WARNING: discarding _NET_WM_PID 5 as invalid for X11 window - use specialized XCB_X11_TO_PID function!
Drive is formatted BTRFS, and I made sure to update to the latest Bazzite Stable build and reboot; no change.
EDIT: I also already tried nuking my compatdata folder and running ujust fix-reset-steam; no change
CPU: Ryzen 9 5900x
GPU: EVGA RTX 2080
RAM: G-Skill Trident Z 32GB
None of the other solutions I have found have either not worked or not applied to me in the first place. Games were all working just fine as of a few weeks ago.