You're on the right path. As long as we continue to use email as a fallback to every other form of authentication, it will remain a single point of failure and a relatively weak one at that.
OP is still correct. No matter what, humans will remain the weakest link...it's in our nature to sympathize and every one of us has distracted/weak moments. It's just a matter of time; look at the guy who runs haveibeenpwnd...getting pwned.