Yeah I always thought World of Motion was kinda bad. But I appreciated Horizons as the Carousel of Progress sequel it was though. I don't put it in the pantheon of really great theme park rides, but I thought it was solid.
From a scenic design standpoint, Horizons had some really brilliant moments. To convey the idea to people who've never done it, I explain that nearly every scene unfolded before you like the "flying over the city" scene from ET. They were all expansive and complex.
Motion was moreso about the tableau. All those "witty" vignettes people love from Jungle Cruise and Pirates and such were the meat and potatoes of Motion.
And also, people tend to think of the theme parks as they remember them "now" - when EPCOT Center opened it didn't have Seas, Horizons, or Imagination (nor World Showcase for a month, but even then it didnt have Morocco or Norway).
Imagine coming into Epcot and before you is Spaceship Earth. Then you can explore the Communicore buildings (which was extremely popular a the time). If you went east, you had Universe of Energy and World of Motion. If you went west, you had the Land pavilion with the boat ride, symbiosis film, and kitchen kabaret.
There was nothing else in Future World. But it was massively popular and had higher attendance than MK for the first few years (which saw Horizons, Morroco, and Imagination open.)