I don't think these are the same. Outlawing CSAM gives law enforcement the ability to shutdown markets and prevent commercial distribution of CSAM. Sexually abusing children is heinous, but sexually abusing children for financial gain is even worse.
There's also the argument that CSAM can act as a gateway leading people from just being a pedophile in their head, to going out and doing something to some child.
There are even people involved in commercial distribution of it that claim to not even be interested in children, just in profit or even allegedly “for a sense of community” (someone actually said this after getting caught, he was in his 20s but I can’t remember his name — he might have been one of the red room guys).
On top of that, while there are different types of child abusers, the worst ones almost invariantly collect CSAM to the point of hoarding. So it really isn’t that bad of a proxy.
The root comment is implying that legalizing or decriminalizing csam would somehow help with prosecution of child abuse? I’m kind of speechless. Csam IS child abuse. The fact that there are consumers encourages producers to, well, produce!