@didnt1able
It is, they don't implement their own encryption like Tutanota or Protonmail, but there is IMAP option so you can use Thunderbird for example to do encryption of e-mails with PGP if you are too lazy to do it manually. We can argue now if that if that is better than other e-mail providers which use their own encryption but I'm not expert to judge that.
@ben_dw