I thought that Lakitu was Asian-American and Shy Guy was black?
In all seriousness, I can sort of (barely) see his point. This is a game meant for people of all sorts to play, and if you happen to be black, none of the characters other than the generic Mii really resemble you.
The problem is, how exactly do you fit a new character in the Mario universe to fill an existing role? The only notable example I can think of is Waluigi, and I doubt that anybody would be satisfied being represented by a Waluigi-calibre character.
The best theoretical solution would, ironically, be to have less human drivers. If there weren't any babies for example, and instead you had Nabbit, Dry Bones, and whoever else, you'd be less likely too feel left out on racial terms. Basically, by removing the game from the issue via dehumanization, you can solve the problem of many humans not being represented.
I doubt this will end complaints about racial diverwsity in Mario Kart, of course. Those are rarely based on reality. But it would kill what little legitimacy they have.
Conclusion: Nintendo should have replaced the Baby characters with Nabbit, Dry Bones, Boo, the Queen Bee, and Birdo to satisfy the hatedom.
Love and tolerate.
