The original question is if you curtail the ISPs rights here, under what legal framework are you not curtailing the rights of NYT/Wikipedia/etc.
Pornography in law is famous because it is one of the few 'I know it when I see it' situations. While certainly the law lacks the rigor we enjoy in technical fields, it is a rare circumstance where that is the legal basis of an opinion.
The original question is not intended to be considered as a rigorous argument, as its author made clear. My point of entry was to introduce a fact that answered your specific question, and as far as I can tell, it stands as such.
While the law, for obvious reasons, rarely uses 'I know it when I see it' justifications, I suspect that that is what most ethical principles ultimately depend on, and to the extent that the law tries to be ethical, the same goes for it.
Pornography in law is famous because it is one of the few 'I know it when I see it' situations. While certainly the law lacks the rigor we enjoy in technical fields, it is a rare circumstance where that is the legal basis of an opinion.