Go re-read the posts in this thread about the physical size of Paradise Bay and the World of Color infrastructure compared to DHS Fantasmic! and the Hollywood Hills Amphitheater. Pay special attention to the stats, and how close Buena Vista Drive is on the north and the natural waterway is on the south of the DHS Fantasmic! facility.
If something on the scale of World of Color would go to WDW, it could only go in an enlarged and rebuilt lagoon at DAK near Everest, the World Showcase Lagoon at Epcot, or in Bay Lake in front of one of the Deluxe Resort Hotels.
Similarly, the Tokyo DisneySea lagoon and their new Fantasmic! is on a scale that is completely different (larger) than DHS or Disneyland's Fantasmic!.