As you go back further in history, essentially everything was decided by violence. But the balance of power has shifted with the rapid advance of technology. Violent behavior is less likely now than ever to make a difference, in my opinion.
And also that’s not what this is. There wasn’t any manifesto, there wasn’t any protest, there weren’t any unions going on strike. It was just one man gunning down another man in cold blood. To what end?
I don’t know the details of why United Healthcare denied so many claims. I don’t know to what extent this particular man had influence or control over those decisions. Despite your blustering, neither do you.
Even if I had omniscient knowledge of the entire process, I am quite certain that the moral liability of this individual human being would not be such that he would be subject to execution under any reasonable justice system. Maybe he did belong in jail, but never in a million years did he deserve to be executed without a fair trial.