That's true, otherwise the movie wouldn't have a point.
I agree about the "goes through something" part, obviously, but sometimes it doesn't change them, or if it does, they might still want/need to behave as before, realizing that they can't change who they are. Know what I mean? I think protagonists chose to evolve or not. That's why I really can't make up my mind about Julien&Sophie's fate, because I doubt they were able to really grow-up and evolve.