Most of these are nofollow or ugc, so the usual answer is they don’t pass anything. But I keep seeing pages that get mentioned a lot on Reddit and forums rank surprisingly well, and I’m not sure if that’s correlation (good content gets mentioned) or if the mentions actually help.
For context, one of my client’s guides got picked up in a few subreddit threads and a Q&A answer. Referral traffic was maybe 400 visits over a month. The page also went from around position 12 to 6 in the following weeks, but we also updated it around then so I can’t separate the two.
Hard to test cleanly, for exactly the reason you mention. What I’ve noticed is pages that get discussed tend to get crawled faster and more often. Whether that’s a ranking factor or just faster discovery, no idea.
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