Comment by CyanLite2

Occam's Razor says that they aren't a lot of black people in STEM positions because companies aren't hiring black people in STEM positions. There are plenty of black candidates applying to FAANG companies only to be rejected because "they don't fit in with the culture" or they "weren't Google-y enough", or "they couldn't write a depth-first-search algorithm in less than 2 seconds in front of a whiteboard ("white board" pun fully intended) so they must not be smart." Over enough time, those parents go on to have kids who then encourage those kids to go elsewhere and invest their study time in other areas where they know they can be successful.