Vico:
A person can give scandal to the weak, and that can intentional, so even mortal sin. From the definitions I posted, if it is a simulated sexual act then it can be called pornography per the Catechism. There are many beautiful things and is may be a sin to enjoy them.
So Rodin’s sculpture can be declared “porn” by someone who is overly scrupulous. I hope it will NOT suffer similar fate as the “victims” of the “Great Castration”. I had the opportunity to visit the Vatican and saw those beautiful Greek sculptures with their original “parts” chiseled off and replaced with some “leafs”.
I understand your point, but the intent of the person is only known to God, and not to anyone else. So no one, not you (or anyone else) has the sufficient information to declare that a text, a picture, a sculpture is a porn. And the “scandal” is in the eyes of the beholder.
Don’t forget, there are three requirements for a mortal sin: it must be a grave (or serious) act, one must be aware that it is a grave act, and it needs to be done with full intent. Any one of these missing, it is not a mortal sin. Venial sins are not important.