OK. You go get every single company, site and service on earth to deploy a 100% perfect credential-recovery system and only have it used by 100% perfect people who never ever make a mistake. And when you've finished, let me know and I'll rethink my approach to email.
You don't need to make a system that's perfect. You just need to make a system in which checks are required to make _any_ change the credentials on an account. Once those checks are complete, it makes no difference if the change is from john.doe@example.com to johndoe@example.com or to jonathan.doe@example.com.
That’s a huge attack surface where if there is even a minor mistake by a junior dev that no one noticed then everyone is going to lose their assets under protection.
