I don't think it's that simple. I actually think a lot of women are also attracted to unkindness, it's the "bad boy" effect. In pickup culture, the well known "neg" is also a manifestation of this.

I think it has a lot to do with a women's personal goals, whether they want to casually date for fun or settle down.

I would really like to see a study of the unkindness and it's effect on women in terms of attraction.