[NotSammyHagar]

I think a better description is using your phone number for 2 factor auth and account means if you steal someone's phone number (via simhacking usually) then you can do anything, because you can reset the account through the phone number, and then you can set the password, and now you control 2 factors (phone + password).

[progval]

That sounds like a bad way to implement 2FA, indeed.