To add to this, I’m also reporting that since a Genshin Patch in June or July (3.8?), genshin launcher and the game just work without any issues. Installed through Lutris, using the normal launcher installation (so not the one that did the patches).

From your report, what command are you using to launch Stardew Valley? It appears to be a bad shell interpretation. Are you using sh or bash? What's the first line of the "start.sh" script? What's your "echo $SHELL"?

I've been using debian testing for years for my gaming PC, for laptops and debian stable for servers. I'm very happy with it!