Whatever pedos can do on the dark web, they will be able to do anywhere else. I always like to remind people that Facebook, WhatsApp, Telegram, and Discord are full of walled CP groups, and it's usually where pedos get caught (at least in my country). You don't need to surf the web to find this stuff, you need to find contacts. Nostr really won't protect pedos more than they already protect themselves. What's stopping anybody from using inscriptions on blockchains that have no authority to upload this stuff? Just apply a filter/mute, file a report, and pray that the offenders screwed up somehow. That's about it. That's the only downside of censorship-resistant platforms and how you deal with it.