It depends on what you need and what the other side has. It is true you can use PGP encryption with proton, yet not with tutanota. However, how many of your friends use PGP? You could also host yourself? This said, on both tutanota and proton you can set a password to encrypt to none tutanota/proton users. Both services are excellent, both lack imap or pop3. Yes proton can do this with a bridge on desktop, but has google services on android where only the app works. Tutanota does that without Google services.

The big question is, what are you looking for? Just a Gmail replacement or PGP capable email. If it’s just for a Gmail replacement have also a look to skiff.com.