> verified through a disposable email address

To the extent it works that's a loophole. I can't speak to proton specifically but the majority of services don't want to permit disposable email because the entire point is to cut down on spam and abuse.

I can appreciate having the option of providing a phone number or email or whatever but I think the state of the ecosystem is telling. The option for anonymous email with PoW per outgoing email isn't provided despite largely addressing the commonly cited rationale for requiring some sort of verification. And we're still stuck bashing PGP, shilling for competing E2E message solutions while it's plain as day that the vast majority of commerce isn't going to move off of email any time soon. Meanwhile TLS can figure out how to distribute public keys via DNS as part of implementing ECH in all major browsers over a period of less than a decade.

How old are the accounts?