Not really a contradiction. Mario Kart could’ve been better as a faster ride. Then you pair it with a no height limit actual Yoshi’s Island dark ride or one based on the main Super Mario Bros. series with us following Mario and Luigi on their quest to save Peach from Bowser.“Why aren’t there any family-friendly Potter rides?”
“Why is Mario Kart so slow?”
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When it comes to Potter their expansion past Forbidden Journey seems very weird in hindsight. The Forbidden Forest should’ve been the dark ride, and Gringotts should’ve been the Hagrid level coaster. I would even argue that Gringotts didn’t need an appearance from Harry and the gang.