Why does the headline focus on the "incest"? It was child porn. I don't think it's even illegal to possess incest porn if it's consenting adults. This guy was into kiddie porn.
The article itself heavily focuses on the child porn, too. It only mentions the word incest 3 time, once at the top (the opening lines are typically a reiteration of the headline), and then twice in the same paragraph later on, but it mentions child porn numerous times. The writer clearly understood what the most significant thing was.
I think this is one of those cases where the writer submitted the article but the editor, for whatever dumb reason, altered the title. That's not unusual nowadays, editors will change titles for SEO and engagement purposes all the time, and I'll bet they're using LLM's to assist now. It's just that usually there's an obvious reason. Take an article one of your journalists wrote, give it a clickbait headline, hit submit. This is odd because it does the exact opposite.
I think the other comment has the right idea: there's a good change search and social media algorithms are hiding or dropping the rankings of titles that explicitly mention CSAM.
There has definitely been a trend in the media of downplaying CP and CSAM recently. I thought others were crazy when they said it, but after paying attention a bit, yeah, it's happening. My theory is that it is because of algorithms filtering stuff like that out.