Section 230(c):
> No provider or user of an interactive computer service shall be treated as the publisher or speaker of any information provided by another information content provider.
Furthermore section 230 (c)(2) states:
> any action voluntarily taken in good faith to restrict access to or availability of material that the provider or user considers to be obscene, lewd, lascivious, filthy, excessively violent, harassing, or otherwise objectionable, whether or not such material is constitutionally protected
So to be clear, it's not that the law is unclear on this, it's very clear on this: The publisher has no responsibilty to consider whether speech is constitutionally protected at all. Not only is there no qualification that these platforms need to meet in terms of moderation, but the law actively states that the platform can moderate speech.