I don't think cloud sync is fully to blame. They probably also should have been using hardware tokens instead of TOTP. There are also password managers like 1P

I don't think cloud sync is fully to blame. They probably also should have been using hardware tokens instead of TOTP. There are also password managers like 1Password and Bitwarden that can store TOTP keys and sync them while still providing multiple layers of authentication (...and hardware key support)