Only if you don't backup your TOTP tokens. Just like you lose your photos when you lose your phone. One of the main advantages of TOTP is that it is portable an

Only if you don't backup your TOTP tokens. Just like you lose your photos when you lose your phone. One of the main advantages of TOTP is that it is portable and can be backed up. > I walk to the local phone shop and get a replacement sim for my number with a few of bits of ID and I regain sms access. Or someone else gets access to your SIM by sim swapping you, which is not as stupidly easy as it used to be, but still SMS remains insecure. Building an authentication system on it is just a bad idea from virtually every angle.