A summary from Star citizen shows pretty much a similar trend.
https://www.instant.ly/report/54a985dde4b0cea5d72c8c2aI just think currently the male demographic Has much more disposable income. I'd take a guess and say that if the average woman playing games is >30 yrs they would be spending money on their House/Kids/Car/Food/Bills compared to the younger age of the male demographic.
Another problem is that crowd funding a game isn't mainstream where most of the women gamers are (and men because hardcore gamers are a minority (yet have huge spending power)) personally i think unless game studio's are willing to spend a fair chunk on advertising, the initial consumer will tend to be male with a smaller number of hardcore women gamers. Then once advertising kicks in the larger female audience will take note. I noticed that trend when World of warcraft first came out, once it got very popular and profitable enough to advertise the female demographic started to take notice. Also by then nerd culture was becoming more mainstream.
I also think that the way we are tackling 'sexism' in video games is wrong, if you look at a female dominated consumer base like (literature) or even tv/film, you will notice the male will be over sexualized. My thoughts is that maybe when using art for covers etc, make the male character appealing to women, currently most Art/pictures of males is tough and bruised ( which appeals to the male demographic), make the male character appeal to women and not focus so much on the female character to attract the women demographic and vice versa for men. When studio's go to con's they should also make use of male cos players. When i go to con's its mostly women who dress up ( a lot of them sexily, not that i mind ^^). If sex sells for men why can't it do the same for women? obviously the game should be more than about pretty people , but people are still attracted to Handsome and Beautiful. Its all about getting that initial intrigue of the game.