You can create a thread about Merit sales, where Chinese merit traders can be reported. They risk red trust by doing so. If they don't get reported, they stay under the radar, as most people here can't read Chinese.

Buying merit will be a temporary thing, eventually all farmed accounts will run out of sMerit to sell, and won't receive new merit unless they create quality posts. Some users could still rank up with bought merit, but the majority won't be able to do that. And as bitperson already pointed out: that's how it is intended.

I checked some of your posts, but if you post on page 34 , page 27 or page 22 of a spam megathread, you shouldn't expect to be merited.

Note that posting generic useless posts in shorter threads doesn't get you merit either. Since the merit system was introduced, I see more bad posts on the technical boards. They get reported and deleted.
I don't think ranking up should be your goal. I know it's easy to say sine I'm Legendary already, but reducing spam is more important now than giving everybody a higher rank.