Also a lot of people think Facebook makes a lot of money off its data but that’s really far from the truth. Facebooks main innovation was letting other companies leverage their own customer data on the Facebook platform by using cookies to cross-reference. They notice their user ‘123’, who shopped for shoes last week but never bought also had a Facebook cookie indicating how they can advertise directly to that user on the Facebook platform.
That is a wildly more expensive ad and it has nothing to do with facebooks personal data. Facebooks secret weapon is not personal data but rather that 1 billion people log in for a half hour per day allowing 3rd parties to reach many of their customers directly.