I understand that PGP might not be the way to go. I understand that metadata might leak. I understand that every cypher will be broken, eventually.
But what's wrong with trying to send a an e-mail with contents you want no other party than the recipient to read, again, provided the recipient doesn't share it with other people.
For the record, I don't send encrypted mail. UX for these is generally terrible, hard to verify sigs, etc. I am genuinely asking what part am I missing. Is there a fundamental reason that encrypted e-mail cannot work with current e-mail protocols? (but replacing PGP if needed)
I recently noticed that some of our federal offices allow to use pgp when communicafing with them. I still think it is an improvement over exchanging unencrypted email with them.
Matrix supports e2ee. Though I believe the only existing implementation is Riot-IM (which actually planned on stabilizing e2ee and making it default today, Apr. 16 https://github.com/vector-im/riot-web/issues/6779).
Also the MLS protocol (https://messaginglayersecurity.rocks/) will likely support federation once it's published, although it'll be a long while before people start implementing and federating it.