I don't see how collaborative filtering fixes any of the issues you and I mention with social media. If I create an account on Netflix and select even one conspiracy theory or junk science documentary I'll be flooded with recommendations for like material my supposed peer group has collaboratively filtered for me. And the more I watch the more I will find. I would posit that life gravitates to local minima surrounded by inviting does lying the unselective in. These insular swamps stagnate and self enrich creating their own ecosystem and cultures. The human propensity for social activity makes it hard to escape - I've talked to many former members of religious cults (which is about all of them IMO) and they relate that first hand.
The current culture of treating knowledge and critical thinking is a depressing trend and stinks of rank centralised control. It doesn't give me much hope can shake up the playing field and and bust out some people from their festering puddles, pools, and swamps of circular and unreasonable thinking.