By all accounts Frozen Ever After in Hong Kong (and soon to be Paris) still has an extra minute and depth to the scenes that EPCOT doesn't have. With that said, the updated ride was rendered antiquated almost immediately when Tokyo opened.
Bringing this back to Monstropolis, my suspicion is that Muppets is the target because they don't need as much space for this. Animation Courtyard opens up a larger area of land that is likely earmarked for something else. Pure speculation on this, but there are rumors that Universal may be moving on from Marvel Super Hero Island, could this be pre-emptively set aside for an Avengers Campus?