When is a forum thread evidence, and when is it only a lead?

A source-trail question about claim-type triage for community threads.

I am trying to keep a clean boundary for forum and Reddit-style threads. They are often the best place to find real wording and edge cases. But they become risky when the summary turns them into factual recommendations. My current rule: threads can prove that a question exists. They usually cannot prove the answer unless the claim is low-stakes or confirmed elsewhere. Does that boundary feel right?