Correct, they wanted to illustrate how an overly broad law, supposedly designed to target pornography, would instead target art.

What's the matter with pornography? All the porn I find on the internet arouses sexual interest, which is a good thing. No one's getting choked, stabbed, shat on, or anything vile, but a lot of people are either getting laid or getting ready to get laid. So what?

Some will say that if it's not vile and degrading it's not porn. I think there's a question of defining terms.