It is possible that my experience is not the usual thing. I have worked for many different managers, both my direct supervisor and the levels above. My line of work has long featured frequent changes in management. I've worked for several remarkably good ones, and a lot of managers who were doing their best with what they had.
The two ends of the bell curve stand out, the great and the abysmal. The great ones were often inspiring leaders -- but even more often, they were men (and a few women) who would roll up their sleeves and do the work, whatever it was. Everyone else would pitch in because, really, what else can you do? There's the boss, hard at work, and what kind of a heel doesn't want to help out?
The bad managers relied on bluster and bombast, on micromanaging the easy parts and leaving the conundrums for the "little people" to work out. They were quick to blame their staff for failures, and quick to take credit for successes. They rarely got their hands dirty. And they could go on in this way for a long time. But it never lasted. They'd either flame out spectacularly in a fit or rage or pique, or they'd fade out, as staff sought better opportunities and they were left with burnouts, time-servers and unskilled weasels as venal as themselves. The drinkers (and drug users) were eventually overwhelmed by their addiction to the point of not being able to function, at which point any decent person can only feel compassion (no matter how unwilling they might be to continue propping up the bad manager). Sometimes, an overheard comment or behavior was enough, if the right person or persons hear or saw it.
Threats, bullshit and histrionics only take a boss so far; built on hot air, fear and fantasy, their efforts eventually collapse, sometimes taking down a department, an enterprise or a government. The bigger they have grown, the worse the fall.
You have to wonder how that's going to play out on a national scale, by and by.