Our society, like many others has only begun to have any idea about the significant numbers of men (and it usually is men) who find children, even babies and infants, sexually attractive.
In the past, excessing images / videos of children being sexually abused was quite difficult. Not any more - it’s at the fingertip on any iPhone.
Someone mentioned upthread that eventually, looking at images won’t be enough. Apologies for not quoting the post and thanks to you poster for raising this. You are absolutely correct. It’s like any other behaviour the individual finds interesting, satisfying, curiosity expands, it’s more rewarding, it escalates, it’s more rewarding then real live children are needed to meet the growing need