A group has become dissatisfied with a monopoly on girl scouting and created a more satisfying alternative. They've taken the responsibility upon themselves to create that which they desire.
Unfortunately, I don't think that's the lesson the Unicorns' parents are trying to encourage.
There's nothing wrong with co-ed scouting. There's nothing wrong with single-gender scouting. Really.
How would that work in camps? Apart from having to have separate times for bathing, obviously.
The wonderful thing I remember from my time was that there was very little status jockeying in our troop. It wasn't like school at all. I felt like I could trust and rely on most everyone.
Now, I'm not sure introducing girls into this would not mess it up. Teenage boys behave differently with women around. Instincts involved are likely much more powerful than mere social technology.
I think your concerns about the dynamic are very valid -- on both sides -- but it's probably useful to remember that the girls and boys specifically mentioned in the article are pre-puberty (10 and 12 year olds, one 13 yr old).