I got it all out of my system years ago. I respect nearly everything George has done. Except removing the Original cuts of his films from being widely available. As for the Special Edition it wore out its novelty pretty quick. But nobody ever argued he did not have the right to fix the films how he wanted. Only that fans be given a choice over which version they want to see.
I would argue some of the changes were valid updating the sound mix, fixing matte lines, replacing cardboard backgrounds. Fixing the shot where the Landspeeder wheels were visible and blurred with vasoline on the lens.
Restoring the image. Replacing the unstable color reversal stock with original negative shots and recombining them. But then he added a bunch of cartoon cgi that aged worse than the original effects, put an awful version of Jabba into the movie, dinosaurs in Mos Eisley Why? He also had Han shoot second and removed some laser burns on a that guy in the black uniform on the death star. Never mind years later making Boba sound like Jango or putting Hayden into Return of the Jedi, or ruining the Emperor scene in Empire Strikes Back.
He had a right to think he did not achieve what he set out to do on the Original production. But preserve for posterity the version that fans fell in love with, and won all those academy awards.
Lucas had a massive impact on Cinema though. You need only look to digital editing, and digital sound or movies shot digitally to see the impact he had on modern cinema. He pushed all the technology forward when few were doing it.