Responsible people did report it to the proper authorities, which is not Facebook.
Reporting it to Facebook so they can take it down and prevent people from knowing what is happening is not responsible.
Yeah, if I for whatever reason stumbled on a live broadcast like this one, I would immediately go to the police, not Facebook. I wouldn't want to risk Facebook deleting potential evidence of the crime.
I own a store that has power tools that could hurt people. As a business owner, it's my responsibility to keep my property secure, and to ensure people on my property don't use my tools to hurt themselves or others.
I install security cameras and I hire guards. I closely supervise customers when they use my power tools.
If I didn't do these things and someone used my tools to hurt people, I would be liable. If I thought a crime had been committed, I would call the police.
But it's not the responsibility of the police to patrol my store. The police aren't responsible to supervise my customers on my property while they use my tools.
That's my responsibility.
If someone uses my power tools in my store to hurt someone, I don't say "pat me on the back, I cut the power to the tools within minutes of the police notifying me".
If I did that, I'd be guilty of gross negligence and reckless disregard for human life, because I could reasonably anticipate my tools could be used this way and I did nothing to stop it.
In many jurisdictions that's a criminal charge sometimes known as involuntary manslaughter.
> If someone uses my power tools in my store to hurt someone,
I think you are unable to separate your dislike of facebook from logic. Let's not pretend that facebook was the cause of hurt, and give the shooter a free pass.