What if: We had support for public key e-mail addresses, something like <pk-12345@gmail.com>. But also <pk-12345@hotmail.com>. With online services treating

What if: We had support for public key e-mail addresses, something like <pk-12345@gmail.com>. But also <pk-12345@hotmail.com>. With online services treating them both as equivalent, so I could login or do account recovery with one after signing up with the other. Google bans me or hotmail goes out of business, and I can go to the other service and authenticate with my private key to open the same account there. Obviously, we'd want some sort of aliasing process so we can have a convenient name, but we probably want mail clients to map those addresses or at least track them with their public key. Could even end up being a shoehorn for E2E encrypted e-mail, which never really seems to have caught on in any big way. This would require some big players to support it to get anywhere, but from a brief thinking about it, it seems solid. Other than that nobody has support for it yet...