Turns out it was a problem with the Steam client itself, I think it’s because the steam:i386 package isn’t used anymore and it’s now steam-installer, but something with the steam update didn’t run correctly. After purging all the old steam packages and reinstalling from Pop Shop it started running again.

Just to add to that, you also have the option of using Flatpak, which already comes installed by default in Pop OS and integrated into Pop Shop. With Flatpak you can usually get a more recent version of the app, but the downside is larger install size.

Worth a try. I should probably switch back to X11 anyway since Slack screen sharing is broken on Wayland for quite some time and it doesn’t look like they’re gonna fix it.