Nope, my argument is "creating child pornography is a crime." It should be prosecuted whether a 40 year old creates child porn or a 14 year old creates child porn.
I understand that if the police are investigating me for whatever reason and they happen to see that a phone number that has never called me and I have never called sent me a 14 year sexting pic, eventually they'll come to the conclusion that it was sent by accident. HOWEVER, until they reach that conclusion, they'll investigate every aspect of my life, confiscate every computer and phone I own, inadvertently or not leak that child porn was found in my possession (years ago won't matter), and maybe find something else completely unrelated that they may prosecute me with.
You're missing the point that teenager is creating something that is so toxic that it could effectively destroy the life of anyone that happens to see it. Who makes it doesn't matter.