I think there is a group of words that means, in one way or another, "serving to perpetuate or defend oppression in one of its forms," that are necessary parts of any anti-oppression discussion, bui that are also often interpreted as insults. "Racist," "sexist," etc. White people particularly get our panties in a twist over the word "racist," or any implication that points to that word, which makes discussing racism with us extremely tedious for many POC, from what I can see. So I think any suggestion that "insults are not ok" would need to have some kind of clarification that calling someone privileged or invoking -isms are not insults, or not usually anyway.