Although I am a dyed-in-the-wool (no sheep jokes, please) hetero, I'd like to comment on this.

Generally speaking, folkies are an odd lot. The choice to embrace folk music is one of selecting a truly alternative style of music. (I remember how disappointed I was the first time I tuned in to an "alternative" music radio station and discovered that folk was not even on the menu! But I digress.) It seems to me that people who have become accustomed to looking at less common alternatives in various parts of their lives would quite naturally develop an interest in folk music.

I can offer no explanation in answer to your question as to why there might appear to be more "out" women than men around the folk scene. So far, I have seen a rather even quantity of both.