That is actually a fantastic reference. It is acknowledged over and over in the text, however, that we do not yet understand the correlation between the genetics associated with race and intelligence. The book also claims that the classic 1970s argument from Lewontin cannot be discarded in light of more recent evidence. We need more evidence.

You may find the paper below to be an interesting read too. It focuses on the social stigma against such research being done but also acknowledges that this is not something we understand yet.

https://www.tandfonline.com/doi/full/10.1080/09515089.2019.1697803

Let's not jump to conclusions.