Honestly, I think a lot of it is that we're in an era of "content overload", if that makes sense as a phrase for it.
The IP mandate is bad enough; it holds back interesting or fresh attraction ideas, it makes so much more about the experience feel like a commercial for Disney+ rather than a standalone theme park experience, etc., all the stuff we've been over a million times. But when you'd see that happen in the old days, it was an era with around one animated movie per year, plus maybe a new Pixar film every couple of years. So, if there was a push to integrate them into the parks it wasn't usually overwhelming and it was often done in a "soft launch" kind of way where they could take some time to gauge how popular the film was and how much cultural impact it had before trying to do anything else with it, e.g. having things like parades and stage shows based on various films before going further with them with rides or anything else.
Now? The streaming era means there's something new all the time, and we get the drumbeat how "this deserves a ride in the parks". But this isn't easy to pull off: when you've got all these different studios within a giant media conglomerate producing content for different parts of the audience and making films and episodic series' and more all the time, you're both going to overwhelm your fans at a certain point.
Worse, it also means that it's harder for a given franchise or film to really become a cultural touchstone that a general park-going audience will all want to experience; even films that make a billion dollars today don't always leave that much of a lasting impression in ways we were once accustomed to in the past, so what seems like a hot commodity this year and a surefire bet to be a long-lasting addition to the parks is a cold product that people mostly shrug off by next year.
