Below I present my own theses about these questions. Please feel free to send me your guesses.
Women like to go out in groups.
These groups prefer to go to mainstream music events, where they could meet people they know. For unknown reasons women don't like to be interested in things nobody of their friends are interested in. Record collecting costs a lot of money and time. Neither money nor time are what most of the women have because jobs for women are badly paid some women have no own money to spend at all because they are married some women have no time because they are supposed to look after their children. For unknown reasons women don't think that beeing a DJ is something achievable.