Because the latest study suggests that girls might as well give up on a equal chance at a career alongside men and aspire to be moms and girlfriends instead.
Funny stuff. My wife works for a major tele-communications company while I stay home, which is becoming more and more common here in the States. My daughter is studying Criminal Justice with an eye on a career in Law Enforcement.
So... I honestly don't know what planet your living on.
A lot of us are living on a planet with a massive gender pay-gap. A planet where women's bodies are objectified and commodified in a way and on a scale that men's bodies aren't. One where women make up 51% of the population but only 10-20% of state legislatures. One where 1 in 5 women can be expected to be raped and only 2-5% of them can expect to see their attacker prosecuted. And on and on and on...
I think Star Trek could make a tiny dent in all of this. A really tiny one; but you've got to start somewhere. Why not on the Enterprise?