You're glossing over the bigger problem. The "person/organization who ought to know about these things" not only has possession of all the data about user behavior on their platforms, they also control the means by which content producers access users.

You're understating the monopolistic power that Facebook's network effects have produced in the online content space.

It's only recently that third party analytics companies came into the space with an incentive and enough data to make meaningful market-wide forecasts.