House of Dragons doesn’t give reviewers with racist motivations any rhetorical leverage. They can’t hide behind arguments that it doesn’t conform to source or canon or anything like that because the original author is leading the creative process.
the original text clearly states that some of the people that are black in the show are white. It doesn't matter that the author is involved, if you are a racist why do you care that the author has been bought to conform to 'the message'.