Two sentences from the article struck a chord: "War matters; love does not. Women are destined to be undervalued as long as we write about love."
I think this is very true. The question is, why? I can see two reasons. One is that women tend to be all encompassing in their tastes. They like love stories and adventure stories. Men tend to be much more one-sided and show little interest in reading stories that are mostly about relationships. You'll notice I said "tend." There are certainly exceptions. But basically, writers who write about relationships tend to find their audiences mostly among women, while writers who write about things like international events and dealing with mortality have both male and female readers and thus have a leg up in the potential size of their market.
The second reason, I think, is the age-old prejudice that says if only women do it, it can't be valuable. If that sounds like feminist whining, just consider the salaries for professionals in female-dominated fields like teaching, nursing, and libraries. Sure they've gotten better lately, but those fields have also become less exclusively female. Jane Green reports she is often asked if she's embarrassed to write chick lit! Do you think anyone asks Tom Clancy if he's embarrassed to write spy thrillers? Maybe we should be encouraging men to write chick lit?
As someone who writes in a genre that deals with the future (science fiction) and with the unreal (fantasy) I consider that the struggle of forming a romantic relationship still offers the most potential for reader empathy. It's one thing we can all identify with, any time any place. Gay or straight, male or female, old or young, who doesn't want someone with whom they can share their life?