Well, it is not rocket science.
If you go to WO or the $100k/push-up challenge topic start posting moon boi messages, you'll farm some serious merits that way. Once you have a main acc that holds considerable amount of merits, you can start building your own alt army and exchange merits between accounts. That's probably what the acc farmers are doing atm. It might sound unreal, non-sense, unworthy to you but some people try it anyway.
You are right some people give merits to short ass moon boi messages a lot and that behavior encourages account farmers but here is the problem, merit distribution is not moderated. Meaning, people can merit whatever post the find merit worthy.
In the end we are almost back to where we were before a decade ago.
As far as I know meritocracy has helped the system a lot to clean it from spammer, and of course some lazy fools aren't here anymore when they sees that the forum is becoming more strict and harder to scale through they all ran away without forging ahead. Usually, Forum is a place to discussed about bitcoin and other life related discussion, so people can share merits to whatever post they found interesting, and that doesn't mean it is baseless or worthless.
For WO, well, I do not regularly visit that board and even if I visit sometimes, I do not comment rather I stick to reading things that are being shared over there, basically I go there to source information and whenever I read things that are worthy I goes off from there, but of course there are newbies or people who are going to source for merits with the intention that merits usually flow there.
So, at somehow, I don't think that section should be disabled about merits because there are people who only base there and they don't have time posting outside of that WO, and if you look them they don't have time or interest to build their account only those who are wanting to build their account and join signature are the people who are that busy spamming that section in the name of seeking for merits.