It must be understood that Harry himself is one of the few Royals whose IQ exceeds his shoe size. Colourism (I'll spell it properly, if you don't mind) is far more subtle than racism, and certain members of the Royal family are as dumb as a bag of rocks. Others are simply nasty pieces of work. Which is why the question was asked in the way it was. Either the querent was too dimwitted to understand the implications, or they were simply being vicious, knowing that Meghan would understand. I have my chief suspects for both scenarios.
Whatever the reson for the question, it is certain that had Archie been 'too' dark, the red-top tabloids would have stirred the pot in the sacred cause of selling more copies!