Although each is appealing to a different audience, both forms of communication use very similar modes of operation and share similar ethics based on selfishness, greed, bombast, an overbearing sense of righteousness, resentment, paranoia and a victim mentality. And, of course, lots of raw hatred mixed in. They will even share similar targets for their hatred -- Women, gays, immigrants, authority figures, etc.
...rap is among the most conservative genres of pop music. It exalts capitalism and entrepreneurship with a brio that is typically considered Republican. (Admiring references to Bill Gates are common in hip-hop.)
Rappers tend to be fans of the Second Amendment, though they rarely frame their affection for guns in constitutional terms. And rap has an opinion about human nature that is deeply conservative — namely, that criminals cannot be reformed.
I would never have put these two together quite like this since I can't stand to listen to either one. But the similarities are striking as the article makes clear.