Reminds me of years ago when American Express came out with their Blue card. You literally had to insert your card in a smart card reader they sent you to make online purchases.

Is the use case that I lose my phone with Google Authenticator, and someone is also simultaneously trying to get into my account? If my phone was wide open and the “perp” has physical access then I guess a yubikey might be my savior, but it seems pretty niche.