That's because Brian Thompson was functionally a serial killer.
From a POSIWID perspective, you are right.
From a "we live in a civilized society" perspective, I can see why some people are outraged about his killing.
Finally, looking at the balance sheet of his accomplishments, I can also see why the pitchfork crowd is cheering.
That is shameful, vicious propaganda. There is no system in the world where everyone can consume all the health care that they want. Tradeoffs always have to be made.
Napkin math puts him at ~5,800-11,500 deaths.
More of a mass murderer in my eyes, but I'm willing to be wrong on that point.