Universal has no motive to give up Marvel theme parks despite Simpsons expiring in 2028. While Simpsons is part of pop culture, the show is way past its prime. There is more current life for Marvel than Simpsons.
Universal is doing tourists going to Florida theme parks a favor by having Marvel rights to certain characters, and Marvel Families instead of Disney. I hate saying that, but it is the truth. The other thing with Simpsons is Universal Studios Hollywood has a Simpsons land besides USF and USH has space issues.
Avengers Campus based on what is open for attractions worldwide is a mess at this point. I know Disney hasn't opened all Avenger Campus rides yet, but what Disney has been doing attractions that were rethemed to Marvel attractions is concerning from a quality standpoint. If Disney gets all Marvel theme park rights, WDW would be getting questionable attractions in multiple parks like MK and DHS at least.
Avengers Campus worldwide has three rides that opened to mixed or worse reviews already. Web slingers is a worse Spider-man ride than Universal has despite Web Slingers being the younger attraction. To top it off, You need to spend extra money for add-on peripheral for the ride that helps riders get higher scores

. Avengers Assemble: Flight Force opened up to mixed reviews as a roller coaster last year with people feeling the theming of the coaster felt incomplete. I read Ant-Man and the Wasp: Nano Battle! is one of the worst rides Disney theme parks have worldwide with it being a much worse version of Buzz Lightyear

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