Remember, the original point of the term “child sexual abuse material” was to distinguish images/video made through the actual abuse of a child, from depictions not involving actual abuse – such as erotic Harry Potter fanfiction, anime characters, drawings from imagination, and the like.
although that distinction lasted about a week before the same bad actors who cancel people over incest fanfic started calling all the latter CSEM too
And it's usually fascists, or at least people who may not consider themselves as such but think and act like fascists anyways.