When I was in my teens and 20s, there was definitely a certain routineness to pedo jokes. It was the aftermath of stories like the allegations against Michael Jackson (false) and R. Kelly (true) along with the revelations about the Catholic church that made it topical during the 90s and first decade of the 2000s. I think in comedy it's always been the only edge left outside of advocating for Islamic fundamentalism or some other form of extremist violence. It's definitely cringey in most cases, but not quite as uncommon as we may pretend looking through 2018 eyes.