I know this is a very unpopular opinion, but from a "maintaining its name as the leader" standpoint Disney's best best is to... expand The Magic Kingdom.
(1) The Magic Kingdom will be viewed as "Disney" by most people, and most importantly it's what they'll
remember as having been "Disney," whether that's justified or not (it's not, obviously).
(2) In order to maintain its standing, "Disney" should blow people away (and they should remember it as such).
(3) The Magic Kingdom doesn't have anything at the impressiveness/immersion-level of World Showcase (impressive, technically not "immersive"), Animal Kingdom (all of it, minus Dinoland), or Galaxy's Edge. I would go so far as to say that The Magic Kingdom is the only WDW park where visitors do
not have a chance to experience Disney at its most impressive.
(4) A major, top-quality new land or two would not only bring The Magic Kingdom back to showcasing Disney's capabilities, but if done right, it could
ease crowding by expanding capacity. Galaxy's Edge did this for Disneyland: the park actually became
easier to maneuver on crowded days.
Nintendo land in California has Disney building a new land at Disneyland.
What land are you viewing as a response to Nintendo?
Despite being nearly a decade late? The original “Potter Swatters” were cancelled.
Is there anyplace to find information about those plans?