If you object to child pornography--and you probably ought to object to child pornography--you object, in part, based on the “child” part.
The age of the actor acting or being acted upon is objectionable, a criteria distinct from recording the act itself, an act you might also object to or might, like so many of the humans, find magnetic, something you wish to see, even see over and over, given that it has been recorded and as part of your net.
For the purposes of moral line drawing, age of those forced to act or be acted upon matters pretty much, the iffy-ness much profiteering includes made more iffy if a child be the source of the profit.
From this you might proffer the question: What if babies were in charge?