I think I can answer some of this
Why not work material around the last dead victim of knife crime, or a baby who’s been raped and murdered. Because the crime is unthinkable, we know how everyday the forst is becoming and how deparved the second is. These days the perpetrator of the first needs help as much as the victim, the perpetrator of the second is unversally condemned (except by those who are equally depraved). We don't need to think that through. Socially we know where we stand.
How about Jamie Bulger? That too is unversally understood, socially.
No matter what slant you put on it when you are dealing with something terrible that happened to a real person with living relatives then it’s beyond low to reduce their suffering to a 5 minute sketch. Unless, like MM there is a pervading sense of bewilderment, lots of conspiracy theories and a nonsensical 'truth' being touted. Then sick, black, insult humour is one way to 'think it through' Not just about the specific instance, but about society as a whole.
In some ways it doesn't matter if you don't loke it, you will at some ppoint in your life have laughed at something similar. You may have felt guilty for doing so... that's the point of it!
Some people embrace it, others get wound up anhd hate it others, like myself, acknowledge that it is part of being human... I don't have to like it, I just need to acknowledge that it exists in us all, me included, and deal with it!
I probably detest something you love with equal vehemence! It's just how life goes!