There is a general feeling almost all people in America (likely the West et al) where if somebody crosses a boundary, you have the moral highground to to dehumanize them. Everyone has their own different line. Chuds and liberals of course base their threshholds off of stupid shit like “you did a crime, now you deserve the punishment.” “Trump’s mouth is Putin’s cockholster.”
American leftists have this problem as well, where once we know somebody is “bad” then it’s no holds barred on what you’re allowed to say about them. That’s how the Vaushes and such form, where racist and sexism is not only logical but moral if you are doing it to a “bad person.”
I don’t know exactly how to stop it, because there are evil capitalist scum out there. But when our “responding in kind” veers into racism, sexism, ableism, etc. then it’s something we need to stop.