My bet would be they're not willing to pay for the actual expertise they need. I bet the fact-checkers FB employs don't have the qualifications those of us who

My bet would be they're not willing to pay for the actual expertise they need. I bet the fact-checkers FB employs don't have the qualifications those of us who fact-check academic publications have; the sheer amount of information FB has to wade through tells me that they need a lot of people, and I have an inkling that they would really resist paying for non-tech expertise that doesn't immediately lead to $$$$. I also wouldn't be surprised if there were perverse incentives for the fact-checkers: Some claims take longer than others to evaluate, but I bet they're on some sort of metric based system. Or that 'I don't know' or 'it's unverifiable' aren't good enough answers even though that happens. I also don't know if FB could GET that expertise at this point: I view big tech more kindly than most information specialists I know and I wouldn't work for FB even for six-figures.