Well, correct me if I'm wrong, but back in the day it never appeared he'd even make the prequel trilogy, even though anybody who called themself a fan knew there was a basic framework of three stories about Anakin Skywalker/Darth Vader. They were not fleshed out in any way. I read EVERYTHING on Star Wars when I was kid in the 80s, and there was NEVER ANY inclination anyone intended to make three prequel films EVER. It was a nice idea that was a what if, pie in the sky thing. No one ever thought he'd do it for real. I believe he was tired of Star Wars then. In the early 90s when rumors started flying about I was totally shocked at first, surprised, and quickly became delighted until it all went to HELL, lol.
But yeah, he just needs to admit that he changes his mind over time. It's completely understandable. I'd forgive him somewhat. Everyone changes their mind on some things over time.