Yeah but that's a personal perspective and motive that you are perceiving yourself, as you can't really decide whether or not the intention of an author was to discriminate certain races by not showing them, or rather hadn't thought about how to introduce a character. It's easy to assume things, and even easier to always think of the negatives, in my experience.
For instance, let's say the author did in fact added a black-skinned character, and represented them in a stereotypical way that showed his personality biased by his "race", now you have a character that I could point at and say "Hey! You're stereotyzing (or however you say that) a black character! That's racist!". Wich would be a dumb thing to say, on the contrary, you can also critique the game and say "Hey! You don't have black characters, that's discriminating!", wich I feel is also stupid, not everything has to be about race, and not every story needs inclusion of every other human group there is. And I mentioned that while it is cool to feel represented by a character for their race, traits, etc. Why can't you feel represented by a human that's not your same race, ethnicity, gender? Instead of judging values, ways of thinking, and judging people by being humans just as we are, we are pointing out their color skin, I'm latino and light-skinned, but I feel represented by asian football players due to their discipline, independent women, etc.