People love to blame the victim for defending themselves over the problematic person who is abusing them, because if they acknowledge that someone is being abusive that kind of morally obligates them to step in.
And they very much don't want to do that.
And obviously the exploitation of users for their knowledge and content so that the owners of Reddit Inc. can gain wealth for sitting on their thumbs is different from the kind of abuse one's mind might go to when the word is raised, but it's the same dynamic.
Someone is claiming mistreatment, those around them are annoyed by the claims, not by the mistreatment, because the person standing up for themselves is putting onlookers in the dangerous position of examining their relationship to that mistreatment.