Yeah, I've heard that I believe it was his wife who acted as master editor, pretty much, saying "No" to some of his ideas, and taking his ideas and pulling out the elements that would lend themselves to a strong story. That's how we ended up with Lucas' ideas in a well told story that pretty much follow classic tropes to a t. Specifically the hero's journey trope. She (or whoever else) took all of Lucas' ideas and molded them in a way that would result in a well told story. It worked.
For the prequels he had a bunch of yes men/women, and nobody really trying to take all of his ideas to try to sort of forge a successful story that goes from A to B out of it. That's why the prequels feel like a documentary - they show us what happened, but not using traditional storytelling mechanisms. So you have a successful thing, but not a successful story. Lucas was more concerned with showing us how events lead up to episode 4, rather than trying to find a story in his ideas, and telling it like a traditional story.
Is any of that really that controversial? It was only after the clone wars cartoons came out that people started "admitting" that the prequels were actually not that bad. Yes, from what I've seen of these cartoons so far, they tell stories from that time period very well. There is proper character development and traditional storytelling mechanisms drive everything. The prequel movies never did, but these cartoons add meat to the story that was never there, which in turns make the movies better in retrospect. But on their own, as a story..