Actually he doesn't say that at all. In fact he said just the opposite, that he had no plans of retconning or undoing anything that happened in the Last Jedi and stressed that the film wasn't a vast departure from the story planning sessions they had to start the sequels off. It makes sense really that he isn't panning the Last Jedi, he was a producer on the film so it's not as if he was in the dark about what was going on.