A local newspaper had instituted separate "I agree / disagree" and "Well / Badly argued" buttons to their comments section. This was, in principle, a good idea. It'd let people clap for things that made them feel nice but didn't exactly have much substance to them, and to recognize well-argued opposing points while registering their dissent. The system was, in theory, excellent.

Of course, nothing remotely close to the ideal use case happened, and banal nonsense was voted as being a good argument because the readers agreed with it, and good, carefully thought out comments got swamped in bad argument flags because they were disagreeable. People just rated on one feeling-valence and nothing else.

In the end, the paper canned most of the voting options, and the interface is left with "reply" and "well argued".

The up and downvotes are not there to evaluate the truth, the cited source of the claim is. No system can be a substitute for the reader to investigate themselves. The things I'm proposing basically just help triage your effort.

Well, yes it could easily be gamed by parties with political interests, but FB's system of fact checking is parties with political interests.