You're not representing the situation honestly
He wanted to have a VP who was a black woman, yes, but he didn't pick her "simply for being a black woman." In the article you linked it states the following:
He said he is getting a “two-hour vetting report” on each of his potential picks, and that he and his team have gone through “about four candidates” so far. “Then, when I get all the vetting done of all the candidates, then I’m going to narrow the list, and then we’ll see. And then I’m going to have personal discussions with each of the candidates who are left and make a decision,” Biden said.
Biden is considering a broad tier of candidates to be his running mate, after pledging earlier this year to pick a woman for the job. CNN previously reported that Sen. Kamala Harris of California, Rep. Val Demings of Florida, Atlanta Mayor Keisha Lance Bottoms, former Obama administration national security adviser Susan Rice and Rep. Karen Bass of California are among the Black women being considered.
So if he started with several candidates and narrowed it down to Kamala Harris, how do you think that happened? Why did he pick her out of the many he started with? If it was "simply" because she was a black woman, why go through a vetting process at all to pick the best candidate? She has serious qualifications and has fought to be where she's at now from what I can tell by her political history. It's many decades in the making
en.m.wikipedia.org
Also, what's wrong with picking someone to be your partner with demographics in mind as part of the equation for why you pick them? Trump did this when he picked Mike Pence to legitimize himself to the Christian base in America when he ran in 2016. Biden wanted to reach out to a voting base that doesn't get much attention, and it seems to have helped when he won the presidency in 2020