As Politech reports, two sections of CPPA were not litigated and therefore upheld. One was the old law that prohibited real children in sexual situations, and no one really opposes that. Another prohibits any "visual depiction that has been created, adapted, or modified to appear that an identifiable minor is engaging in sexually explicit conduct."

"Identifiable" here means an image that's made to look like a specific, real child that can be identified. There's an argument that such fake images are still harmful to the children, and that may be more permissible than the same argument would be against an adult (other than civil right of privacy claims).