Leftists really think that white Southerners are all conspiring to insult black people, that spiting black people is what white Southern life revolves around. Probably because spite is what drives leftists, everything they do is an underhanded middle finger, so they assume that everyone else operates the same way.

That's why they (at least the lower-tier lefties not pulling the strings) were unable to comprehend the Unite the Right protest and thought "good people on both sides" was a racist dog whistle. It started out as locals just wanting to preserve history.