> the weakest link will usually be at the other person's end (and out of your control) By that logic, no one should ever switch from an insecure service to a s

> the weakest link will usually be at the other person's end (and out of your control) By that logic, no one should ever switch from an insecure service to a secure service. The advantage of being backwards compatible with email is that you don't lose anything by upgrading, and for some messages you do gain something. (You shouldn't change your behaviour based on a false sense of security, though). Ideally, the person you are communicating with would use PGP, for example if their provider is ProtonMail, so you could have end-to-end encrypted communication without having to worry about keyservers or encryption settings. Unfortunately, however, Tutanota has chosen not to use PGP because of fears of "attacks from quantum computers"[0]. Of course, their own proprietary system is vulnerable to those attacks too, but that's a minor details, and you should ignore it... [0] https://tutanota.com/faq/#pgp https://tutanota.com/faq/#pgp