It's good that GP posted that. I didn't initially clock that it was AI slop. Their message prompted me to look at the poster profile, which immediately showed this was a bot. That in turn meant I downvoted that message, which increases the signal that it's a bot. The community has something to gain from it. Downvotes are not strong, visible signals. A message it.
How can you downvote anything? I see not such button on my HN UI
Flagging != downvoting, be sure to actually flag. Flagging & moving on or emailing is the advice of the guidelines. I don't think replying is something GP should have been downvoted themselves for though.