Mail.app is the only thing really keeping me on macOS. I won't use mutt and there are, to my knowledge, zero good (non-phone-home) good GUI mail clients for linux.
I'm happy to be corrected on this point, if you have knowledge.
@sneak Why don't you like mutt? Just prefer GUI or ? If term apps is OK and not a fan of mutt, there is aerc that is pretty neat, though minimal.
@sneak have you tried Evolution or Sylpheed?
@sneak I use Geary (https://gitlab.gnome.org/GNOME/geary/), but it lacks some features and mantainer (last I checked), but graphics wise I think it's quite pleasant.