You get what you ask for with LLMs. In this case though there were no children talking to the chatbots. It was all adults talking like adults but saying they were kids. This was in order to produce the result they wanted (something LLMs are very good at providing, if you ask correctly). It is not a surprise that the bots talked about what the adult humans told it to talk about. Would these same topics have come up with kids? No.
This is pretty much, "I bought this hammer from Facebook. Look what happens when I use it to hit myself in the head." ... "OMG! Facebook's hammer hit me in the head! I'm shocked! Think of the children!"
I'm saying kids talk about subjects kids are interested in. And in the vast majority of cases, they're not going to be talking about the explicit sex stuff these adults were. Sure, there's going to be precocious kids, some exceptions, but as a rule, yes. Kids aren't going to be doing this because kids don't have the biological motivations to do so. I remember being a kid.
And just to head off the obvious response, yes, I guess a 17 year old is still technically a kid. But that's not what people are worried about here. Let's not conflate.
This is pretty much, "I bought this hammer from Facebook. Look what happens when I use it to hit myself in the head." ... "OMG! Facebook's hammer hit me in the head! I'm shocked! Think of the children!"