Robber barons bought dozens of medieval European buildings – where are they now?

There's not actually a way to fix this - you aren't going to get rid of the concept of power itself. If you try to "educate" decision-makers, you're just contributing to the problem: all you do is replace the slice of reality that was contributed by someone else wanting to influence them with the slice of reality that you want to influence them with, and then someone else can get mad. It's up to the decision-maker herself to seek out accurate, independent, non-biased information, because most information volunteered to them will be biased. I think many of the "tech elite" actually do this - it's to their advantage, after all, since what they don't know will lead to them being replaced by a new elite. Indeed, the problem is somewhat self-correcting: as old elites become progressively more powerful and less informed, smart & hungry technocrats start looking at them as rubes to take advantage of, and they end up being replaced by people with a more accurate conception of reality.

My point is just that objectively speaking, power hierarchies seem a lot flatter now than they did in the late 19th centuries. Nobody has died yet because a tech startup founder hired an armed militia. Investors today complain about how they influence the market and buy software to minimize that influence, they don't actively try to corner or manipulate it (well, outside of Bitcoin and Porsche). The Vinod Khosla flap would barely have made the news 100 years ago, he would've hired armed guards to keep the surfers out and that would've been the end of it. We've made progress, as a society, in the last 150 years: it's slow progress, but progress nonetheless.

> The Rhine river hills are covered with the castles of robber barons who took protection money from ships.

How exactly does this differ from "taxing"?