[29athrowaway]

Yubikeys are secure, but the most popular second factor is SMS, followed by authenticators, which are better than SMS in my opinion.

MFA does not imply bulletproof security.

[ssully]

Well since this discussion is in a thread about 1password I think it's worth pointing out that 1password doesn't even support SMS as an MFA option [1].

[1]: https://support.1password.com/two-factor-authentication/