>>819279998A combination of novelty avoidance and the image generated by hip hop.
Novelty avoidance is a psychological phenomenon that has varying intensity in individuals. Some people are novelty SEEKING, and if it is unusual from their normal life they will expressly interact with it, even preferentially. Wiggers come to mind. Most people are, to certain degrees, novelty avoiding. If it's unusual to their daily life, they'd rather not interact with it.
Black culture as portrayed by hip hop is anathema to the typical white family, and for many white people it's the primary window into the black worldview. They might enjoy observing it, they might find some enjoyment in the music, but they would never willingly participate in it. It's also demonstrably corruptive to black youth, and many white people have a story or 2 about a casual interaction with a black person who willfully and non-ironically displayed the hip hop mien - arrogant, aggressive, entitled, poorly spoken, and ignorant. Coupled with novelty avoidance, such behavior reinforces a negative view of the black population in general. They see a representation, they assume "That might be a unique case," then they encounter an example of that representation, and it shifts over to "That might be a general case," and now they have a perfectly rational reason for avoiding interactions with black people, or having a negative viewpoint of them.
ThePornDude