At first the reports were successful, but when they started to go unhandled I gave up on reports. Realistically, all of these posts should be deleted, but whoever is behind it is obviously counting on no one to waste their time reporting dozens of posts every day.
I stopped following the user and reporting his posts for the same reason. I still have some of my reports unhandled, and they are probably from that time, and you are right that he wouldn't get tired of making such posts but he is sure that people would get tired of reporting them unless he gets punished for it but unfortunately, a person doesn't get banned for shitposting.
More than 2k posts and only 5 merit received so far tells me that it is very unlikely that this guy plans to grow this acount for sale (in that case he would be way more efificient and his post history would be much different).
Imho it is just a shitposter who is trying to build some activity until he applies for a altcoin bounty campaign or something along the line.
I had the same thought at first, but then I thought that there is a possibility of him having more, higher ranked, accounts where he has enough sMerits that he can circulate within his accounts to rank up over time which is why he doesn't care much about his post quality because it is evident that he is doing this only to hoard activity points and there must be a reason behind it. No one with a right mindset would waste their time shitposting in a forum without having any benefits attached to it.