state is, ideally, composed of elected representatives

oligarch-led private armies oppressing people.

They're the same picture.

Elections are a venue for competiting oligarchs - US elections are largely just a wealth check - with the bonus that afterwards people feel they've chosen their oligarchs and are less likely to notice that 90%+ of elected representatives only represent the interest of elites.

I do the same thing at work when I need mentally ill people to do what I say. "You can do what I want version A, or do what I want version B, which one?" always works better than "Do what I want!"

I agree that violence management is a very difficult problem with no easy solution. But I don't think giving full control of legitimate violence to the rich is the best solution, which is what a state of elected representatives does.