That human beings, or a portion of them, like to change their external look often enough. Maybe not in every society on Earth, but surely in many of them.

This reminded me of that famous scene from The Devil Wears Prada: https://www.youtube.com/watch?v=Ja2fgquYTCg

I can understand that it is basically impossible to live separate from that sort of industry but that doesn't make it not nonsense. It's a very good scene (and a nice movie), but it doesn't change the fact that "fashion" is a moving target that exists for it's own sake. It's a signaling pathway that sprouted an enormous industry on it's back.

Which parts are nonsense?

The part where things are changed for no good reason.