Honestly it’s kind of just Lucas’s narcissism thinking that everyone would just blindly follow what he had laid out for them without having ideas of their own.
I sort of agree but I also think if it’s narcissism, it isn’t entirely unearned. He handpicked Kennedy, and chose to take the company to Iger. He spent the last 5-6 years essentially feeding story ideas to Filoni & Co, who consider it a personal point of pride to be Lucas’ conduit for ideas becoming reality. And before all that was the prequels, where he didn’t exactly have a squad of Yes Men rubber stamping everything he thought of, but he also made it a habit to essentially tell everyone who raised a concern that it didn’t matter because it was his company and ultimately he was going to do what he wanted anyway.
But I do think that the Clone Wars experience might have led directly to his believing Abrams and Arndt (and then Kasdan) were just going to carry his water the way Filoni did. That Clone Wars experience probably fooled him into believing that’s how ALL his hands-off projects would go. That it was owned by Disney wouldn’t make THAT big a difference. They’d still have the meetings once a month and they’d sit around a table and listen to him bloviate about the Force and take his word for what Star Wars is, etc. etc.