Trump threatens to 'close' down social media platforms

There's an unsolved conundrum I haven't heard mentioned yet.

After the 2016 election, there was a thought that too much false information is spreading on social media. This happens in every country and across every form of communication - but social media platforms seem particularly worrysome (and is particularly bad with Whatsapp forwards in some Asian countries).

So what should the social media companies do? Censor people? Disallow certain messages (like they do with terrorism related posts)?

They settled on just putting in fact check links with certain posts. Trust in the fact deciding institution will of course be difficult to settle. No one wants a ministry of truth (or the private alternative).

So the question remains - do you, or how do you lessen the spread of misinformation?

Media literacy and criticism classes in middle school?