TLDR: He thinks Mario Kart is a conceptual failure of an attraction. Not like Supercharged bad or anything, but he doesn't think its well executed. He does agree though that regardless of his criticisms, the ride will always be popular.
Nintendo (and Universal Creative but mostly Nintendo) was so stuck on if they could, they didn't stop and think if they should.
They absolutely NAILED the land on all fronts, but I really don't know what happened with the rides.
I really hope we're able to ride without the AR in the Hollywood version.