Have you ever been to the dark net ??
The worst hidden sites are very well hidden, I must say. I accessed via Tor a few times, but I just gave a look to the dark wiki index. There are plenty of websites that appear to be offline. I recently saw a play-through about a game where the character has to surf the dark web, and it said some sites can only be accessed at specific hours of the day or night, so I wonder if that also happens in the real dark web.