Have you ever recommended a friend or colleague for a role or hired off of an outside referral? Is all the value in social proof and how well you know the referrer, or would you take a recommendation from an anon account that had verified referrals to other top companies? What is missing to turn the hive mind into the best recruiter?
What makes a good teammate is so subjective that any objective measure will be gamed before you can say "Goodhart's law". A proper evaluation of a candidate necessarily turns into a hunt for indirect signals where if you say loudly the name of the information source, you will banish it in the abyss of good stuff gone to hell. That's why resume driven hiring works for low-level positions and when you really have something to loose, the recruiter seeks and evaluates a candidate much before the first face to face.