Let me stop you right there.
That's not going to happen. Murder is as old as the beginning of time. Even when there were only four people on Earth, one found a reason to murder another.
It's like nutty climate activists who think they can control the whole universe: you can't control the human behavior of even the 325 million people in this country, let alone the 7.7 billion in the world. If find these pie in the sky "Oh let's DO something! We can prevent it!" discussions pointless and naive. You can't prevent crazy.
No one is saying anything about stopping all murders.
If there's a "but isn't it worth trying" thing, helping those that can be helped before they become murderers seems a pretty good place to start. There's absolutely no expectation it will stop all murders, but it may stop a lot.
Rage at finding your wife in bed with your best friend, or your husband in bed with his best friend, or your boss not giving you that Friday off you asked for TWO MONTHS AGO, KAREN are still going to lead to murders. Great Uncle Nevermet, who is worth $10M and leaving it all to his only remaining relative, but is hanging on at 83 and
refuses to die of natural causes will still lead to murders.
But, maybe (just maybe) "my neighbor's dog said I should shoot up blue-haired old ladies as they exit the Presbyterian church this Sunday" might just be reduced. Just maybe.