Putting aside things built in the last decade--because too soon to tell--the iconic Disney rides are not IP based. Most of the IP rides are forgettable rehashes of the movie. The one exception may be Mr Toad, a long-forgotten movie much better known as a theme park attraction.
UOR did not have the luxury when it chose the path it did. Virtually everything they do is IP based. I think it's telling the one ride that isn't--RRR--is arguably the most iconic in the park, despite its lackluster reputation as a coaster. There's a double level of nostalgia--you have to be nostalgic for the movie, and then for the ride. Very few rides at any Orlando park can make that claim.
Also, I think the most iconic IPs are those that embody cultural archetypes. Sleeping Beauty was never a hit movie for Disney, yet castles, a dragon and a prince with a sword are easy to understand even if you've never seen the film. Similarly, as much as I like Jurassic Park the novel and the film, it only works as a land because dinosaurs are a primal interest to children, not because of Chrichton's scintillating plot. Original Star Wars checks off those archetypes, but I'd argue Madagascar does too (not the first time a cowardly lion has entered the public conscience). That doesn't mean both are equal as entertainment, but it does mean both are better suited to theme park attractions than, say, Shrek or 101 Dalmatians, both record-breaking hits in their day.