I’m all in for retconning the term “Sith” in the OT. I always wondered why they aren’t mentioned or named in the original trilogy, knowing the Sith Order was present in the early drafts.

And besides, despite we all thought the sequels would ignore the “Sith” denomination (because of its prominence in the prequel era), then TROS arrived and mentioned the Sith more than any other film. So it stands out a bit that the Sith aren’t named for the whole middle chapter of the Skywalker saga.