Does it work if you launch steam through mangohud? Like:
mangohud steam-native
You would probably want to temporarily remove the per-game launch command while running it that way, for the HUD to actually show up in game (assuming it will load). But that’s another approach to try, at least for troubleshooting purposes.
I haven’t seen anything really discouraging out of Infomaniak, either, for e-mail and drive services. Been using them for a while now.