Think about it this way - predators like to go where their prey is at.

It's not that, in the previous centuries the Catholic Church had a problem with pedophiles - the problem was the Church was educating a lot of kids, so if you were a pedophile, the Church was where you wanted to be if you wanted access to kids.

Today, the school system is where pedophiles are - it's not that teachers are pedophiles, but instead pedophiles seek to be teachers to gain access to kids.

Bluesky is just signaling to people, hey, if you wanna spread CP, this is where its at, so the CP creators are just naturally, willingly going over there because they know their audience.