If one can distinguish a “genuine racist” from a “trolling jerk” based on who they target, and if we treat “trolling jerk” as harmless, acceptable malice, then it seems to me that the most effective tactic for “genuine racists” to establish themselves in communities would be for them to use racial slurs as much as possible and then claim, when confronted, that they’re only trolling.

This does not seem to me to be a desirable outcome.