One of the fundamental patterns of the universe is that power tends to aggregate.
Black holes pull more matter towards themselves and gain ever more gravity; a large tree keeps growing and blocking out more sun from the understory; empires gain more resources; rich people attract more money; and Medium writers with 32K Followers get more views, and more followers.
You are on the right track when you talk about the banality of evil. But I think it is a dangerous error to call it evil.
The only real evil in the world is pain, and the only goodness is happiness. Power is merely the means by which pain and happiness occur. Power itself is not evil. And when you call the wrong things evil, it makes real evil harder to identify - and ultimately to fight.
The tendency for power to accumulate is not evil - it is just a property of our universe. But that said, the accumulation of power does make the universe less democratic. And a less democratic universe means fewer of it's constituents are able to successfully defend themselves against pain - which is a bad thing.
The biggest reason why power accumulation is so out of control today isn't capitalism - it's globalization. Globalization is what allows the rich to be soooo much more wealthy than the rest of us. And globalization itself is largely caused by our technological capacity to travel and communicate easily over large distances.
Obviously, technology provides huge benefits (i.e. relief from pain), despite it's enabling of globalization and power accumulation. So eliminating technology probably isn't the answer. I don't know what the answer is, but simply calling the wrong things evil in order to prove that we are morally superiour isn't a good solution either, and it ultimately just muddies the waters towards a real solution.