Because in my experience, that sort of lazy ad hominem is most frequently practiced by people on the left of the political spectrum. The reflexive Fox! Fox! Fox! is a classic example.
...and yet "lazy left" isn't a frequently practiced ad hominem in your world? In other words "lazy left" == "Fox! Fox! Fox!"
Racist rants should be universally held up for shame, but the media - especially the proudly left-leaning outlets - are absolutely duplicitous on that subject.
Are you honestly trying to tell me that if a group of blacks was chanting overtly racist remarks they wouldn't be called on it by whites? but then I suppose things like "black lives matter" is probably racist chanting in your world.
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