I'm actually surprised that's the case. I'm not opposed to a willing adult making or consuming pornography, but honestly I don't see how most of it does not "appeal to the prurient interest" and "lack serious literary, artistic, political, or scientific value."
That only leaves whether the material is "patently offensive" which is probably what is most open to interpretation.
That only leaves whether the material is "patently offensive" which is probably what is most open to interpretation.