Also, if we talk literally 20 years ago, Freenet was at infancy, still used arbitrary human-readable content keys that were supposed to be shared externally —
https://web.archive.org/web/20000817234626/http://unicast.or...
— and web pages were only a proposed option (with Javascript!):
https://web.archive.org/web/20010405191438/http://freenetpro...
You are probably thinking of more mature days of Freenet version 0.5, which, in its turn, was a network independent from Freenet version 0.7 (2008—present). I've seen 0.5 when it still ran in parallel, and can't remember the content being way too different in general. Still no child slaves for sale.
The days where many people posted stuff just for the thrill of being able to post something illegal and disgusting are long gone — partly because the communication structures in Freenet evolved, so such stuff will quickly make you invisible to most people (since most people subscribe to moderation that hides that).
I never said that a central slave market was on Freenet. I don't even think the protocol would be a very effective way to do it due to how slow and unreliable the protocol is at retrieving things. What I meant was that images of this stuff were available in large galleries, and the previous messaging system before Frost would auto-find new forums for you at random. Frequently they would be large galleries of images of this stuff.
So have fun with whatever you are expecting me to pull out of 20 years ago links that are like however many 40+ hex digits long. I haven't used Freenet since I saw that stuff. Not really sure why you'd think I would keep links to it or I would have a photographic memory or even would actively seek out the stuff.
I'm not sitting here saying I contributed, I'm saying I would play around with Freenet, even submit some harmless static HTML pages for fun to test the protocol. After the messaging system started popping up forums that I didn't find acceptable, I deleted the client and never touched Freenet again.
The burden of proof is not on me nor you. This is a conversation on the internet not a spontaneous scientific journal nor an inquisition.