For example, I could L1 trust people to evaluate papers and the trustworthiness of other users, and L2 trust others only to evaluate the trustworthiness of papers. If I notice a spurious signal getting in, I can find out who it came from and prune my list of trusted users.
I imagine I'm not the first to think of this. Anyone know of reading material on the topic?
(Journal clubs are groups of people, usually working in the same field, who pick & present a paper to the rest of the group on an rotating basis.)
I haven't seen more attempts at similar things, which doesn't mean they don't exist though. (There were mentions of a similar feature being added when Elon Musk was about to buy Twitter, but just gossips)
An advantage of having open peer review system is also that this kind of attempts could be detected by tools doing automatic processing of scientific knowledge graphs generated by peer review activity.
This, coupled with verification of users, should be able to minimize the risk quite significantly.