Why all the uproar over possible changes on Disney theme park rides like Jungle Cruise?

Over the weekend, action star Dwayne “The Rock” Johnson roiled the Disney fans community with an Instagram post from Walt Disney Imagineering headquarters in Glendale. Last month, Disney announced that Johnson would star in a live action film based on its theme park ride, Jungle Cruise.
To help prepare for the role, Johnson was getting a tour from Disney’s theme park design team, but he also dropped the news that “we’ll partner with Disney’s brilliant Imaginee