I'm sure this came from a salesman at a law enforcement expo who has been selling these to every community in the country. It suggests a national narrative where the police are convinced that people are plotting to kill them at every moment, and even if none actually have, it's only a matter of time.
Every encounter with police begins with hostility. You know they're armed. You know they're assuming you are, too. I can only imagine how that's magnified for people who "fit the profile" solely because of the color of their skin.
https://www.spokesman.com/stories/2020/jun/05/architect-of-c...
I mean look at Law and Order, or Chicago PD, or Blue Bloods. There's a token episode about police brutality or corruption that is "solved" by the "good apple" standing up to them.
I'd be willing to wager the source of violence in police|public interactions is the public in less than 5% of interactions, probably less than 1%.
Your comment only addresses dead, not almost killed as the comment you are replying to.
In all these cases, watching the amount of damage someone has taken can easily cause ptsd.