That’s literally not how any legal system works but ok.
You don’t jail someone because you’re concerned of “what else they might be up to”.
I see in another comment that he was found out while under investigation for something else entirely.
To answer the grand-parent: the victims of this behavior are yourself and the society you live in. The answer to "what happens to my virtue and my relationships if I indulge in AI-generated child porn?" is not "nothing", and the society which tries to experiment with this will reap the whirlwind.
Fake child porn. Or do you think the real victim of child porn is morality, and the abused children are such an insignificant detail it's not even worth distinguishing between fake and real child porn?
https://old.reddit.com/r/midjourney/comments/16w12j8/just_a_...
Why is this bad? Well, let's look at how one might fight child abuse: find lots of CSAM online, put it through facial recognition and other digital forensics, try to find the children involved, or see if the IPs sharing it are plausibly involved with children, or use sting operations where police pretend to be children online. Then use regular policework to follow up. In the end you may end up saving a child from a very bad situation.
Now how do you fight "sexualizing children"? I don't know, awareness campaigns? Go after porn artists drawing young characters? Make a classification office, such as in New Zealand, to decide which media gets censored... maybe eventually you'll catch someone actually abusing children, but your target is so vague, your efforts so unfocused, most of your manpower is wasted.
To give an analogy: In a campaign to ban dumping toxic waste into rivers, you are the person saying "actually this is the fault of capitalism, we should fight that instead".
You definitely do not fight sexualizing children by normalizing the production of child sexual abuse material. Come on now.
And yes, if you allow for the spreading of child porn, you approve of it with your silence. If, on the contrary, you believed it were wrong, it would be your duty to do something about it, such as making it a crime.