I’ve seen transcripts of these online conversations. The cops give the perps numerous opportunities to back out and go away. They’ve even gone as far as warning the perp that what the perp wants is illegal. The creeps that get snagged in these stings deserve everything coming to them.
Sometimes the cops do, but usually they don’t follow the guidelines, they arrest people that try to back out, they go on adult websites and say they are of age and get someone hooked, sometimes they even encourage the chat towards sex, sometimes they harass people until they agree to meet.
It’s not all black and white.