You don't need to train on pictures of canine golfers to make highly convincing pictures of dogs driving golf carts on Mars. https://imgur.com/a/EIWUJYp The AIs are extremely good at mixing concepts.

I don't think that's necessarily true.

An AI can generate an image of a wizard with a frog on their head and that doesn't imply that the training set had such an image

Are you sure? I’d guess that AI can extrapolate from adult porn and non-sexual depictions of children.

So the AI will generate children with adult private parts?

Pretty sure there are non-sexual images of naked children too, such as in anatomy textbooks.

Unknown. For example, I have heard most offenders abuse their relatives, and I don't expect synthetic material to have any impact in this category.

Also, the only way to find out if this has any effect at all (positive or negative) would disgust and outrage many, as that test would require having a region where it's forbidden and a control group where it's allowed and seeing which is worse.

I'm not sure how many people would try to lynch mob (let alone vote out) whoever tries to do that, but I'm sure it's enough that exact numbers don't matter.

My guess is that offenders abuse relatives because they are easier to access and manipulate, not because there is a true preference there. More a crime of opportunity than a pursued goal.