I don’t think it was the NSF directly (though their research could have been utilized), but the US did try to do something about it (at least with COVID misinfo). But then the whole “ConSErvaTivE voICEs aRE beINg SilEncED!” peanut gallery whipped themselves into a frenzy.

• ‘Facebook Files’: Fact-Checking Jim Jordan’s Claims Biden Pressured Facebook
• Mark Zuckerberg’s letter about Facebook censorship is not what it seems
• Content Moderation At Scale Is Impossible: Some Republican Politicians Are Indistinguishable From Neo Nazis
• Research Finds Conservatives Vastly More Likely to Share Inaccurate Articles Without Even Reading Them