The #1 is true - but I don't really mind. SMTP is tragic at this - even if the egress is perfect and over TLS - Tuta & Proton are getting my mail unencrypted at the ingress and only then encrypt it with my private key for the rest of the journey. Now - I DO believe them they do so perfectly - but do I "really" know 🤔? If it was me - I am giving every phone a public ipv6 address and running mailservers directly on phones but that is everything but an elegant solution🤷.