TL;DR
Install an archival version of Bazzite or whatever else that corresponds to a date when you know it worked correctly.
Bazzite in particular makes this fairly easy. They have straight forward instructions on how to roll back to a given version.
If that fixes it, just use that version and don't update.
If you want to stick with Cachy, you can use the Arch Archive to downgrade your entire system to an earlier date, or just Gamescope.