I guess Psycopaths have always been in power.

Not always but eventually and inevitably.

Clawing one's way up the ladder of wealth and power requires the ability to make decisions and follow courses of action that will bring harm to other people, so the competition favors those who are not impeded by morals, ethics, principles, integrity or empathy. So regardless of how they might start out, authoritarian systems are inevitably captured by psychopaths.

And always will be.

No

Authority is for children, and is only colorably necessary because humanity has only managed to advance to the equivalent of adolescence, and still needs mommy and daddy to keep them from doing stupid things.

Given time, humanity by and large will continue to advance psychologically, sociologically and philosophically and will eventually reach something akin to adulthood, and then will have no more need to live inder the care of mommy and daddy state.

Claims of authority work because people submit to them. Even the most ruthless and despotic tyrant can't hold authority if the people simply refuse to submit.

I think Sam and the morden Estin class is the best we have ever gotten

If one was so inclined, one could also pick out a "best" serial killer or child rapist.

I'm not so inclined.

Bcoz mostly they are peaceful

Whether you die unnecessarily from a winter power outage caused by an overburdened and undermaintained electrical grid, or from a denial of healthcare for a treatable condition, or from being machine-gunned in the street, you're still just as dead.