Recently I am seeing he is leaving neutral feedback to others for low quality posts and as he is taking it as a matter in his own hand. He could just report the low value posts to the moderator and could have a personal note for himself using a plugin created by TryNinja.
All of the other points before this aside, leaving a neutral feedback for a shitposter is acceptable and in some cases desirable. By putting into words on a member's trust page just how bad of a poster he/she is, you're (hopefully) warning campaign and bounty managers that they won't be a good prospect.
I've left those kinds of feedbacks plenty of times, and if you look on my trust page and see what I've left for people in the years 2016-2017 there will probably be zillions of neutrals related to post quality.
I think JollyGood is willing to listen to advice and change his habits. I'd like to see him remove all of those feedbacks that have nothing to do with anything forum-related. Neutrals are another story, though. If you ask others, they'd probably tell you that a neutral is the way to put a note on a member's profile. Not a big deal.