Yeah Vader was supposed to be one of many Dark Lords. As per the Lucas/Foster story conference on Splinter, and in the novelization of Star Wars. That part was never edited out of the book itself but the audio tape abridgement changed it to just Vader being the Dark Lord. in the 1990s. John Whitman did the edited abridgement.

Rather than rewriting or having a new novelization of Return of the Jedi it just became non canon. Since Obi-Wan isn’t Owen’s brother in the prequel. And it wasn’t Obi-Wan’s hubris that lead to Anakin becoming Vader. Leia remembering her mom. Yoda wasn’t his Jedi Master.

Honestly the prequel itself should be struck from canon its done too much damage to Star Wars, even if i like Phantom Menace and i like Qui-Gon.