Are you perhaps confused because I mentioned the Communications Decency Act? It's true that one of the purposes of the CDA was to regulate pornography on the internet (although I don't think it was about child pornography--the pornography concern was about children seeing pornography on the net), but those parts of the CDA were struck by the Supreme Court in Reno v. American Civil Liberties Union, 521 U.S. 844 (1997).
The CDA also, in section 230, said that providers and users of interactive computer services are not to be treated as the publisher or speaker of any information provided by another information content provider. Section 230 was not struct down in Reno v. ACLU, and remains in force.
(2)Civil liability No provider or user of an interactive computer service shall be held liable on account of—
(A)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; or
I just try to interpret the laws as they are written with my limited legal experience :)
That said I think I can agree