The majority of the people doing the threads have been following it. If there is a couple that aren't they're the exception. Some people take a bit to get around to the other games or dont announce that they have given feedback in the thread and instead just give it on the page
Imo I see the rate for rates and the behavior you want of people possibly rating others who rated them as pretty much the same. Theres just a tradeoff with the extra things that come with it along with that. Rate for rates main downside is that not everyone does them yes but on the other hand with the people rating others that rated them, that also is rare even in jams where rate for rates arent common so the same overall problem arises just in a different form. A lot of people dont sort random and play a random game to then give feedback on because the majority of the time its not given back and then they cant get ranked in the jam as they wasted all their time. The only reliable sort where its the case of being able to get feedback back reliably is sorting by most karma, popular or by the highest rated as those games tend to be active in the community but even then thats still funneling the votes into a small subset of games.
Rate for rates is a way for people who may otherwise not be seen to show their game to some people and collect some feedback while also returning the same thing in kind. Sure if somebody abuses this and rate for rates to get 100 votes that may be an issue but again its a small subset of those are actually doing the rate for rates, its just more noticeable as you see them in top rated and you are seeking them out (confirmation bias).
I agree in an ideal world this should not be the case but its not an ideal world and mechanics exist in itch that people use