I think it's more like it's uncomfortable to just sit there and digest that you're part of the Bad People, and say nothing about it, and then also say nothing about it when other people affirm that you're part of the Bad People, so you sort of have to just passively sit there if you don't join in on hating the Bad People as well (which is why people do it). I theorize white-on-white racism is a coping mechanism developed to prevent awareness of systemic racism from developing into a form of genuine self-hatred due to awareness of one's own complicity in it. While normally the obvious solution would just be to stop being complicit in it, people are not very rational beings and might perceive themselves as still being complicit even when they actively aren't, leading to continued usage of the "Death to All Crackers" shibboleth as a kind of OCD ritual to affirm oneself of their own purity in front of Communist God (ironically, an urge probably primarily spread and codified by white people). I do not mean this in a pop culture sense of OCD, I mean in the genuine sense of it being fuelled by a pure-O compulsion loop.