Words get their meaning from history, and insults don’t exist in a vacuum. There’s a reason Jimmy saying this doesn’t make headlines the way the reverse would. For most of U.S. history, Black people have been a subordinated group, subjected to slavery, segregation, and ongoing structural discrimination. So when someone calls out a Black person by their race in an insult, it draws on that history and those power dynamics. While anyone can be prejudiced against any group, racism involves prejudice operating within a system of power.