Freedom of speech has ~2 definitions in the US... first, the legal definition (with the Constitution and related case law). A second, the general notion of bei

Freedom of speech has ~2 definitions in the US... first, the legal definition (with the Constitution and related case law). A second, the general notion of being literally free to make speech however/whenever one wants without intrusion for anybody at all (government or otherwise). In this case, we're sort of at the edge of the legal definition. Social media can be viewed as the modern version of the town square (can be, isn't 100% proven out in law yet). If one takes that statement as valid, then the government cannot regulate speech through social media without a very good reason. But, minors don't have the exact same rights as adults for various reasons (guns, alcohol, privacy at school, etc). My general impression (IANAL)... the government can likely limit minors' speech on media platforms, however that limit would have to very specific and tightly defined so as not to deny speech to adults. The devil is in the details (implementation)... the legality probably hinges on what method is required to verify age.