I think it’s useful to stop thinking about TOTPs as a multi-factor implementation, and think about it as a forced random password. The biggest problem by far i

I think it’s useful to stop thinking about TOTPs as a multi-factor implementation, and think about it as a forced random password. The biggest problem by far is that people still use the same password everywhere, and no amount of yelling at them for the past 20 years seems to be working, so the only solution is to declare passwords as mostly broken and force people to use TOTP. That’s effectively how most sites are using it anyway. Using this approach, you now have a probably weak password of a certain length, and then a guaranteed random password of 6 digits that expires every 30 seconds. The brute force window is essentially closed at that point. This approach also reconciles the idea that a TOTP secret must be tied to a device, instead of a person. I’m pretty security conscious and can put up with a lot of shenanigans to be more secure, but the insistence of TOTP apps to not allow backup or transfer of secret keys is just too much for me. I can’t imagine any regular user putting up with that, and the result is the help desk has to deal with many requests to remove devices when someone gets a new phone. With the threat model redefined to force the use of unique passwords, it makes it far more acceptable to store TOTP secrets in password managers.