Responding broadly to other comments here...
tldr; If an anonymous system is can't protect sequences of bits you abhor, it can't protecting your sequences of bits either.
--
Freenet is a solution to a problem many people refuse to believe exists, and therefore is mostly only used by people that are either at least a bit paranoid, or are actively persecuted. As long as people favor convenience over privacy, or have zero qualms about having their lives monetized by others while seeing little to no benefit from forfeiting their individuality, freenet will almost never be used for anything that is not frowned upon by the mainstream.
Yes, the first thing critics will do is point at child abuse because it's an easy straw man. But for a counter-point, check out some of the Japanese release boards on Frost or FMS. Byte for byte, there's probably more unoffensive anime raws being dumped into freenet daily than all of the CP that has ever existed on the network. The perceptive difference? There are no frequently updating freesites being created for those inserts, so you have to know where to look to find the keys.
--
The idea of the Darknet was supposed to keep people from feeling icky about Freenet. You only connect directly to friends, and you're not friends with pedos, right? User base never grew large enough to allow organic growth of the network that way though. Maybe with better tools...
--
The main reason people shit on Freenet while holding up Tor as some pure and noble effort is that they can buy and sell things over Tor, while Freenet has no profit incentive.