This is a poorly justified solution to a real security problem, which is the elimination of password logins. The author assumes that the weak point in logins is

This is a poorly justified solution to a real security problem, which is the elimination of password logins. The author assumes that the weak point in logins is the password hash, and rarely if ever is this an attack vector in modern Linux. Disabling password logins, moving to SSH public key based login and hardware tokens (such as the SSH private key stored in Yubikey) is a much better solution than the one proposed here.