Yeah, I was going to post the same thing. I see people in skirts riding their bikes in Chicago all the time. It is so normal I would never even give it a second thought.

I don't think the author has ever lived in a city, and is associating "Europe" with "city" instead of "city" and "city". (Oslo is kind of treacherous for cyclists anyway. Ride into one of the tram rails and you are likely to go down pretty hard.)