I think there was the possibility in 1999 of crafting a trilogy in the Clone Wars era without relying on many of the previously named characters, a story which would expand the Star Wars universe and people’s imaginations. Unfortunately Lucas went in the opposite direction and made a story which was over-reliant on name recognition and under-reliant on story. Remember that the ONLY thing that the prequels needed to be was to be designated as 1, 2, and 3 and come before the OT in chronology(and they didn’t even need to be that). There was no requirement that the prequels be connected via character or theme.

Unfortunately after Lucas made it clear that the entire saga (1-6) were going to be about the fall and redemption of Anakin Skywalker, people then assumed that Skywalkers must be involved with every numbered episode. Now if someone proposes remaking the prequels without Anakin or Obi-wan, the story feels incomplete or misguided. This is the power of framing. Lucas was allowed to frame the discussion in terms of Anakin, and the only way that most casual viewers could see past the framing is if they were given a trilogy which was as imaginative as the OT without including these well-known characters.

Furthermore, if any alternate trilogy was made, it would be incredibly jarring to the general audiences unless the alternate prequels were made in continuity with the Lucas Prequels, since those are the films people are aware of from that time period. You would ironically be REQUIRED to make an alternate prequel focusing on Anakin and Obi-wan just to ‘set the record straight’ on their relationship before venturing into uncharted character territory.