Come on!
If your son or daughter married a person of a different race would you not ask what features any baby might have? It's a natural question and one that most of us would ask, even privately. It's not "racist" FCOL just a very normal question... and that goes for all parents, black or white, whose offspring marry a different race.
I don't like the Royals, and never will, but this is just a media-fest to hurt them, and possibly an attempt by Harry and Megan to do as much damage as possible. The 'leak' was no mistake, somebody did it on purpose. It will help sales of the book, though...