"there is no enumerated power who's original intent was to enable Congress to mandate the seizure of pornography by state or local police."
True, but because that power is not specifically forbidden to the states or the "people." As per the 10th ammendment, states can ban pornography and the Supreme Court should stay out of it. It was only "activist" judges that stole that power from the people.
But that's not what's being proposed by the people in this article.