Social proof just means herd behavior where animals that don't know what to do in some novel situation simply take cues from their peers and do what everyone else is doing. There is nothing at all inherently positive about that. Just in humans, mob behavior, witch burning and pitchforks and all that, are all examples of people acting on social proof.

In fact, the exact opposite concept of this could exist, scrape Twitter for consumers to show them who they shouldn't do business with, and it would still be social proof.