Oof. Yeah that would be frustrating to deal with. If something like that ever happens again and they don’t stop after you asked them nicely just put them on ignore and if they keep doing it for an extended period of time report them for it.
What they are doing may or may not be actionable but that’s up to Blizzard to determine. I’m sure it depends on how long they are doing it and how often they do it but if they’re never reported then they’ll just keep on doing it.
Definitely lesson learned though to not engage with people like that. He might have been trying to get a rise out of you specifically to bait you into saying something they could report you for. Don’t take the bait.
Ignore, report, and move on.
Good luck with your appeal. And if the first repeal is rejected, you can appeal again until they say no more appeals. Even if the suspension is already over it’s still worth it to appeal if you don’t think you did anything wrong as penalties stack so the next one could be more severe. Though in your case you already know you used language that is against the rules, so this advice might be more for next time since it’s unlikely any appeal would be successful (but only Blizzard can say).