Harris is the first ever Announced Affirmative Action (AAA) candidate ever on a presidential ticket. It is well known that triple A selections, with their inherent elimination of 7/8 of the population, wind up with lower quality results than any process that includes all possible selections. Voters aren’t so stupid that they don’t notice this.
Sorry, but vast numbers of voters ARE that stupid, and the Rat party and their propaganda wing are more than happy to exploit that stupidity. If they are told enough times that Kamala is black, they will believe it and they will vote on that basis.