I work adjacent to game dev and this story is so common, you would be shocked how many cool projects die because company politics get involved before the fun stuff even starts. Concept artists pour hours into ideas that executives kill in one meeting without even playing anything. Disney specifically has always struggled with letting their universes touch each other, and it took Kingdom Hearts succeeding for anyone upstairs to loosen up even a little. Sad part is by the time they warmed up to it, gaming trends already moved on to something else. This kind of stuff makes me appreciate leaked concept art way more now, at least we get to see what almost was, even if it never left the drawing board.