With the prequels, he traded the integrity of the original trilogy for lowest-common-denominator crap that the kidlets would clap their Popsicle-stained mitts for. When the guy in charge says shit like "Jar Jar is the key to all of this," you can sadly conclude that the visionary has lost his vision, like so many other kindly old grandpas.
Except he didn't lose it, because that vision was always "keep children happy above all else."
Except the ones who got this empty box for Christmas. They can go to hell.
Remember: The first (fourth) film wasn't intended as the opening (middle) of a grand epic. It was simply Not Flash Gordon, Wink Wink, a straight-ahead, good-over-evil standalone sci-fi flick meant to "give kids a sense of values." Lucas couldn't give less of a shit if 40-year-olds considered Yoda a great philosopher of the ages. And speaking of Yoda: He was never supposed to be in Return Of The Jedi. The only reason Lucas wrote him in was because he thought of the goddamn children. He regularly consulted child psychologists, one of whom strongly advised that an outside character confirm to Luke, "Yes, that dickhead who Lannister'd your hand really did sire you. Have fun at the reunion." Why? Because without the thumbs-up from a character they trust, kids under 12 would very likely have dismissed the plot twist as the bad guy being a lying asshole to the good guy.