The second way is to use one time pads in addition to passwords. Who needs a smartphone when you can use a piece of paper. Mind you this can be copied so has a

The second way is to use one time pads in addition to passwords. Who needs a smartphone when you can use a piece of paper. Mind you this can be copied so has a similar vulnerability to passwords. But since it can be generated you can think of it as a salted password when combined with a classic one. And then we use the final way of authentication, hard to forge personal documents, government issued... often in poor ways. Computer systems cannot be truly fully trusted. Final security always depends on the human operators and equivalent human impersonators. A skilled social engineer can even convince your friends the account is dead. They can call the delivery company or even initiate the procedure to reissue documents or destroy keys. They can phish and scam you which is even easier.