I'm not much of a gamer, yes, but where in modern gaming you see actual portrayals of racism and sixism? And not just badly educated loonies - those two things used to be foundations of our societies.
Where in gaming in general have you ever seen portrayals of genuine racism and sixism, and it in't just used as a shorthand for "this guy is dumb and or bad"? And for that matter, where in gaming have you seen a realistic portrayal of a romantic relationship? How about parenthood? Heck, you'd have trouble finding good examples of a lot of those even in other mediums. Even in movies that take place during times in US history where we still had slaves you'd be challenged to find a hero who didn't treat slaves like equals.
I don't think it has anything to do with "political correctness" persey. Writers/developers/whatever what their audience to have a particular emotional attachment with particular groups. Look at the Stormcloaks vs Imperials choice; that whole issue hinges on both sides being equally good or bad. There isn't supposed to be one side that someone could point to and say "they're completely in the right." But if, say, the Stormcloaks were all super sixist and racist while the Imperials were all about equality, people would pretty quickly decide that the Stormcloaks are bad and the Imperials are good, even if it was subconciously. It wouldn't matter if the racism/sixism displayed by the Stormcloaks was "realistic," people today feel (rightly so) that those things are wrong. If you want to get readers/viewers to have a particular emotional reaction then you MUST acknowledge how they will react to certain ideas/reactions.
So I'd say it's probably less "we need to have gender equality or we'll get in trouble" and more "everyone would think these people are bad guys if they were super racist and sixist." Notice how the Thralmor are the most outright racist group in the game and they also happen to be a group we're meant to dislike.