So one should configure an alternative user for each group of permissions that any arbitrary app might need? Then what happens the day that I do decide that my weather app should access e.g. my location? Now I should move all its data and update my launch scripts to the new user?

I happen to dislike snaps as well. The hard coded install directory is a passion point for me. But at least the permissions issue they are getting right.

I wish that desktop distros would adopt the Android permissions paradigm.