Just like I think we need more varied "weak" male and female characters, that perhaps become strong.
Of course, there's another side to this. Most key people of game development teams right now are male . It's difficult to write about a gender you've never been or really experienced. It takes more research and understanding to write a role outside of your experiences or comfort zones. There are games that make an attempt to have a strong female lead and just fail horribly.
You also don't see many gay leads, and virtually no (intended) transexual lead characters for this same reason. And when there are notable gay or transexual characters they're seldom displayed in a positive light, because most of the world still thinks it's okay to make fun of the gay guy/gal.
On a side note, I really want to see some more really good female (human) villians/antagonists. We seem to be lacking some in recent years.
Games, and other media, are often a reflection of current social values desires. This is why people place so much emphasis on little things like female characters. It's easy to shrug it off as "it's just a game." But the game isn't the issue, it's the people who make the game, the society that makes the people who make that game, and the ideas that are reinforced by the messages in that game.
I'm not one of those "gta makes people murderers" types, don't get me wrong here. But it does portray certain values like distrust of authority, individualism over all, brutal competition and more. And we, at least in america, often experience each of these ideas. Some may find the values they already had within a game and use them as justification for their own values.
A person may not necessarily hate women, but is constantly exposed to an enormous amount of tropes that are harmful to the modern woman seeking equality which will only give the current patriarchal society more weight.
My four cents.