The social media sites are going about censoring fake news all in the wrong way.
First, their entire business models are based on numbers of users and length of engagement, not on "truthfulness" of content, however that is defined.
Second, FB, Twitter, Google, etc. are in no position to determine which of the billions of submissions are factual. They can barely police which are incendiary calls for government overthrow or violence. Twitter can't even tell fake accounts.
There are better ways to determine fake news.
Third, the social media sites should not be put in a position of rubber-stamping whatever MSM media sources, or worse, government authorities, tell them is "truthful." That just leads to subcontracting of ministries of propaganda to private companies.
Fourth, the social media sites ought to be doing something to rank people by reputation, as determined by verified user rankings, A.I. assisted traces to primary sources for tweets, posts, etc. This way people would really know where information is coming from and hopefully not post anything that's been red-flagged as suspect.
We are in danger of getting a sanitized, MSM-approved version of the news. Many of the so-called alternative news sites have uncovered major news events in the recent past. Without a free internet, we may never know what we don't know. Crowd-sourcing was how most internet media sites were originally supposed to operate. Perhaps the best known example is Wikipedia, and that seems to be as reliable as the top-down sources Encyclopedia Britannica, and a lot larger. It's time for the social media companies, which thanks to unpaid user bases in the billions, to start trusting the users that made them the behemoth companies they are today.