While I completely agree with you, I'm not sure that's really anything new. The Disney parks have been doing that for decades. Epcot got Captain EO and Hollywood Studios got Star Tours... Both of which could be found in Disneyland's Tomorrowland. I've always felt Hall of Presidents and Carousel of Progress would fit in just fine in Epcot at the American Adventure and in Future World.
It's all at least somewhat interchangeable if you think about it. I mean, "Future World" is just a synonym for "Tomorrowland" after all. Horizons was the spiritual successor to Carousel of Progress. Mission: Space is the next evolution of Mission to Mars.
Hollywood Studios can always use the excuse that something is *based* on a movie, even though so are most attractions in Magic Kingdom (most notably in Fantasyland)... and Epcot's Future World can always use the excuse that something is based on sci-fi, or contains elements of wonder or inspiration.
At the end of the day, Animal Kingdom may very well be the most unique Disney park left (in Florida.) Especially since nothing there is duplicated in other parks around the world. (Is it really nothing? None of its rides or shows are in other parks? That can't be true. Even Finding Nemo the musical? I gotta look that up.)