I believe he is saying that stereotypes exist for a reason, and it's true.
Companies developing and marketing products absolutely bank on it, and if it didn't pay off for them, they would change their approach.
Marketing is intentionally racist - meaning that they make decisions on who to target based on factors such as race. I remember taking a marketing class in college and being a little shocked at how non-PC some of the material was, but that's the way it works. You can throw all of that pretentious "we're all the same" philosophy out the window in the real world.
"X" group shares enough of the same beliefs and behaviors that if you cater to "X" group, you are going to sell more stuff to them, and develop more loyalty to your brand.
Which is fine if you just consider games a product to be sold to the masses.
But seeing as games are such a big part of modern culture, I think it's foolish to ignore those who don't fit into the convenient marketing categories.
