It's an on off fashion thing.

I have 2 pairs of those pants, but they are my fishing pants. That means I wear them while chopping a path to a fishing spot. Then I zip the legs off and go for a swim when it gets too hot to fish. They are also made from a material that dries really fast.

But they are purely utilitarian. My partner thinks I look like a dork in them. But they aren’t there when I zip the legs off and get all sexy alone in the woods. Lol.

How can pant legs be high fashion?

They're low fashion.