Planet of the Apes was a gigantic challenge, making the clothes work so people could do stunts and action in the clothes. I really learned a lot about that in that movie.
The designs were based on quite a lot of research of what a movie musical is, filtered through the eyes of today. If we'd gone strictly with the '20s, the movement would have been impaired.
The reward is that you can actually create a world separate from reality with a story, actors, music, and camera design. When it works it can entertain, move people and teach us all.