There's actually no such thing as "misinformation". It's a completely made up concept. There's just information. a la: "Look, this person said this. Here's another person, who said something else." All of this is just regular old information.

In publishing, editorial makes some amount of sense because the brand of the publisher is staked behind the claims being made. But in social media, it's the personal(/account) brand that is staked behind the claim, not that of the social media company. For example, ISIS doesn't get an editorial column in the NYT. But they can have their own page on FB & Twitter.

These companies are existing in a magical reality where they are able to exercise complete control over what can and can't be said, and garner no liability for when they use that power to promote falsehoods and stifle the truth.