>Yes, it move the single point of failure to the user's email account That is already the case for the supermajority of people. They use one email account for

>Yes, it move the single point of failure to the user's email account That is already the case for the supermajority of people. They use one email account for everything and you can simply "Recover Password" on various services once you gain access to their email account. Not many people purposefully use unique, individual email addresses for every single service they sign up for...