Well, I wouldn’t say it’s because genre per se, in so far as it’s because cishet white male is “default” in society. People see action and, without something to give a different context, we (and I mean we as in western society at large, regardless of our individual natures) have been conditioned to percieve cishet white male it’s why…
Right, and I think this may actually be a significant factor in why there are so many games genderlocked to male. Many authors do the exact same thing, and, in absence of a reason to do otherwise, they just make the PC presumed duplicates of themselves. (Of course, it can’t be the only explanation because at least one game genderlocked male was written by a woman, but I think it’s a major factor.)