[dane-pgp]

> Fact checking creates a history of this which should feature into algorithms.

At first glance, it looks like you've just re-defined the problem from "platforms should decide which posts are true" to "fact checkers should decide which posts are true", but actually I think you might be onto something.

Platforms could use their existing user-reporting features, and measures of audience size, to inform fact checkers about which posts are the most controversial; then different fact checkers could (reactively) investigate the claims and offer rulings that would appear as a banner over the relevant post.

The missing pieces of the puzzle are that individual users should be able to opt in to one or more fact checker, and platforms should give users a default set of fact checkers, and the fact checkers should be funded by a 1% tax on platforms' revenue (split in proportion to the popularity of those fact checkers among users).

This could actually be a valuable and viable system, and maybe the sciences could also benefit from a system like this for flagging suspect papers and paying for researchers to attempt to reproduce results. It could even be gamified, with researchers winning "points" for correctly guessing which studies have non-reproducible results (as long as these points didn't have financial incentives attached which could corrupt them).