Is it just me or does TOTP for two factor auth seem like a step back to the days of digest auth where you have to store the symmetrical secret in a reversible manner. Passwords stored in plaintext were--and still are--rampant and there have been myriad high level exposures of these secrets by even the largest entities.
Aren't we now just delaying the inevitable exposure of the TOTP secrets along with the vulnerable databases of user information being compromised by increasingly skilled attackers?
In a world where we have hardware asymmetric crypto engines in almost every device used for 2fa how has this method of authenticating a device become the most popular?
With systems like Secure Element and Touch ID hardening key access with silicon and biometrics we have access to security that even government actors struggle to compromise, so much so that they are moving towards legislation to weaken it.
Storing derived keys has been best practice to protect passwords at rest for at least a decade, but this strategy can not be used to protect the TOTP shared secrets. This leaves symmetrical encryption, which even when implemented properly is of dubious value in protecting live systems. PKI has been around even longer and yet it still struggles to gain a foothold in implementation space.
It's still the Wild West in most respects and a roiling crap shoot of kiloword RFCs and flawed implementations. Are there any existing simple to use systems that leverage the PKI tech available today to to securely assert device identity for 2fa on internet connected system that may need to be critically secure?