 We're science fiction and fantasy fans, and our media nowadays tends to be made by geeky guys who grew up watching Star Trek and Doctor Who, and all of whom secretly want their own lightsabers.  Some of them are really, really good at creating, writing, and developing female characters.  Some aren't.  In general, when they write female characters as actual people, given actual development and interests and goals and opinions and lives, we say, "Frak, yeah, she's awesome!"  And still, the writers are mostly guys, and while the guys are peripherally aware of rape and battery and pay disparity and the Mommy Wars and all the other things that inform the day-to-day lives of women, they don't have to live them and they don't have to think about them unless they want to.  While they may even have been personally touched by sexual violence, they haven't, for example, spent years talking with friends about what happened when they were drunk or drugged or otherwise coerced into sex, and they can, but usually don't, bring that background onto the page and into the characters.  Traumatic, life-changing experiences become jokes, and the ages-old "Well, she deserved it for wearing that outfit / being out alone at night / believing him" is at best addressed in a metaphor with vampires but more typically doesn't even make the cut in character motivatons except in shoehorned revelatory backstories about childhood abuse.  There isn't the understanding that fear of rape is present, in whatever small doses and buried under however much denial, in every woman's daily life from the day she's old enough to know what it is.  It informs clothing choices and activities and dating partners, and while those writers capture the form of it, very few grok that the fear extends towards the male heroes too.  So we see a fantasy world that resembles ours, but with off-kilter differences, and sometimes that's a good thing – Dr. Merlin watches cartoons preferentially because sometimes a Y-7 safety zone is the best thing to maintaining one's sanity – and sometimes it's a reminder that, to half the population, we are often as exotic and incomprehensible as Moon maidens.

That doesn't mean men can't write female characters.  That doesn't mean men shouldn't write female characters.  It means that any given male writer is, from time to time, going to screw up writing about women, that he's going to get called on it, especially from female fans who have seen these same damned problems before, and that he's going to have to decide whether to get defensive or fix the problem for next time.  It means he's going to have to stand back and see the world from the point of view of someone raised female in a culture that celebrates masculinity and denigrates things associated with femininity (while fetishizing particular body parts, as if those are not part of the whole). 