It is different when it is a well-known thing. If you see "toor" in a BSD password file, you know that's a BSD thing and not someone making a backdoor. I'm wi

It is different when it is a well-known thing. If you see "toor" in a BSD password file, you know that's a BSD thing and not someone making a backdoor. I'm wildly guessing that the BSD flavors that have toor have patched their password DB manipulation utilities and APIs such that when you change the root password, the toor one changes with it and vice versa.