I would like to disalllow home folder access and network access for all snap packages including and especially the ones that will be installed in the future. So that no snap package could read my files and send them somewhere ever, not even one second between installation and disallowing access manually. Is it possible?
This is not currently possible, but has been suggested in the forum:
...while I understand why x11 and home are automatically connected (lots of apps would have a poor experience otherwise), I’d like to override that for my own machine: upon install, I’d prefer if such interfaces weren’t automatically connected, and I could connect them if I wanted to.
Unfortunately it appears that this idea has not left the discussion stage.