The object is very clear in the fight against racism; you have reasons why you're opposed to it. But when you're writing a novel, you don't want the reader to come out of it voting yes or no to some question. Life is more complicated than that. ↗
I am not opposed to the limited use of polygraphs in a case where a person is suspected of wrongdoing. But widespread use of the polygraph as a screening tool goes far beyond what is acceptable. ↗