You bring up some good points. As a true-crime fan and writer/YouTuber, I try to always keep that fact in the forefront: this really happened. Real people suffered and died. The point is justice — how it was served (or not), and maybe even how we can try to ensure it doesn’t happen again.
True-crime fandom represents something criminologists recognize as an essential element of societies, that of coming together to denounce crimes and criminals. It offers not only a catharsis, but reaffirms and strengthens a society’s rules and its commitment to serve justice.
We’ve *always* devoured stories of murder - the grislier, the better. From the time of the first mass-printed circulars, the most popular papers were those that luridly described murders, complete with illustrations. My grandmother used to devour Ellery Queen and Alfred Hitchcock’s Mystery Magazine — while they were fiction, every story was about someone getting murdered, and how they were eventually caught (or not).
Sure, for some, it satisfies a rather morbid curiosity in a safe and socially approved way. Others (like myself) are fascinated by the ways that detectives and scientists work to solve these crimes. But for most, those stories serve as warnings, or ways to understand crime and, hopefully, how not to become a victim of it.