I don't really think all movies need character development to be good, I mean it's definitely important in say, a character-driven drama film, but in a zany screwball comedy horror movie for kids? not so much.

Beetlejuice has a very silly premise which benefits from brevity, I think diving too deep into the characters would make the whole thing less fun and bog the movie down in terms of pacing. it's really important for a movie like that to maintain a sense of momentum, and that's very hard to do with a long runtime