Joss Whedon, creator of Buffy the Vampire Slayer, on his theory of "womb envy:" "It's a very simple theory and I gave it a silly name, but basically it just seemed to be a fundamental thing that women have something men don't, the obvious being an ability to bear children, and the resilience to hang in as parents. I don't understand why or how anyone ever pulled off the whole idea of "women are inferior." Men not only don't get what's important about what women are capable of, but in fact they fear it, and envy it, and want to throw stones at it, because it's the thing they can't have." [Mother Jones]
It's very nice, but still remarkably patronizing, especially to women who do not bear children. The "aw shucks, I just don't get how sexism came about" shows a profound ignorance of history and the move from matriarchal to patriarchal societies, something that too many surveys of history completely overlook or simply see as the "march of progress".
Men and women both contribute to the creation of children, and can both play vital and important roles in the upbringing.
To be honest, I find Whedon's "rah" third-wave approach to feminism more than a little ridiculous. His shows feature young women of almost precisely the same twee body type whose whole lives are defined by romantic entanglements, sexual abuse and dysfunction. His next show is about people being mind-raped. For all his efforts there's some dark territory when he writes about women.