History has it that Zuckerberg designed the social networking site for the purpose of rating boobs, but if his overall social goal was to help the intellectually lazy out themselves as psychologically unhinged, he hit a grand slam.
I wouldn't even limit this to Facebook. Any social media that allows people to talk as "equals" or behind a veil of anonymity allows for crazy conspiracy theories to thrive in communities that present themselves as immune from crackpot theories. Most of the time, on sites with a less diverse user population (I'm classifying Facebook as having a very diverse user group) the right-wing conspiracies get dismissed simply because the users are more liberal. Yet after the Snowden leaks I notice a huge influx in the number of conspiracy theories floating around sites like Reddit and Ycombinator that framed in a wholly evil, all-knowing organization. Things like "Micheal Hastings was assassinated by the CIA" were widely talked about and accepted even though the evidence was circumstantial at best. They are communities that claim to be above the theories, yet they embrace them when they explain something that is confusing to them. So while the article talks about Facebook and climate denial, recent my recent experiences online given me doubt that any community is immune from conspiratorial explanations, especially when they are one the "losing" side of the news.