I had a similar experience, but their response was better. I had been talking on a certain sub for months (an illness support sub...) and there was one user who was prominently abrasive. Actually an odd mixture of acting tough mixed with seeming very sensitive, so I suppose basically a bully. We didn't get along great. He liked giving factually incorrect advice mixed with telling us all we were "weak pussies" for being concerned about illness. I don't remember all the details, but at some point he started blatantly using alternate accounts to support his viewpoints and harass people. I called him out on that and he was angry about it, and started saying things like "I'll be in Portland next week, maybe I'll come pay you a little visit" and "you'd better watch for me, I'll be seeing you soon". Reddit admins did remove his main account along with the 2-3 others he was using.