Because what one looks like is infinitely unimportant as to what they bring to the job they are hired for (unless that job is acting a particular role in a movie).
Also - if you had a child who needed heart surgery, would your primary interest in choosing a surgeon be the color of their skin ?
Did it ? If it really did, then it was obviously wrong and racist.
This method of establishing a racial and gender litmus test for a specific nomination doesn’t actually indicate anything about the candidate themselves, as it actually obscures proper consideration of their actual pertinent qualifications. It does speak volumes about the judgement of the individual selecting these superficial traits, as the primary factors for nomination, and the racist and sexist attitudes of those advocating for same. And this will leave a stench over the nominee, no matter how qualified they actually happen to be.
Anytime a superficial criteria is announced ahead of time, as an over riding criteria, limiting the pool of potential nominees for consideration, it leaves the question of actual qualification hanging over the nominee. It doesn’t matter which political party does this. It is nothing more than one of those well meant intentions paving the road to hell.