This "I'm never going back!" conversation is a little different if we're talking about Disneyland, where there are just so many attractions and so much value in every corner of the park. If the worst case scenario were to happen and Disney announced Cars of the Caribbean and Haunted Mater re-themes, I'd be angry and would no longer want to give this company any of my money -- and yet there'd still be so much value elsewhere in the park.
At Magic Kingdom, when you replace Splash, Country Bears, the Rivers of America, Tom Sawyer Island, the Liberty Belle, Mr. Toad, Snow White's Scary Adventures, all the green space and trees in the hub, and (mark my words) Hall of Presidents and Liberty Square and the Liberty Tree Tavern... at a certain point, what else is really left? Or, what does MK offer that Disneyland doesn't also do 5x better? It becomes pretty easy to say you're never going back.