All three of the Star Wars movies were very much George Lucas films. He nearly went bankrupt trying to get Empire made. The idea that he had little to nothing to do with the creation of Empire is inaccurate. He didn’t have complete creative control on the first two, but he was definitely the driving force.
George Lucas contributed his part and that’s what he was good at. Not more. Anyone who thinks he actually had a clue what was going on in that movie, well just look at the '97 Special Edition release. He changed it to make Luke scream when he jumped ffs. The man didn’t even have a basic understanding of the story.
As Carrie Fisher said in an interview once, the actors and the story often just got in the way for George, who wanted to focus all of the attention on the creatures and robots he made up.