Charlemagne exhibited control and influence over a smaller chunk of Europe than the current E.U. The U.S. can almost bankrupt any country at will by freezing it out of the banking system and imposing sanctions.
At the risk of being pedantic, I think it is you who doesn’t understand the word corrupt. The US bankrupting nations it doesn’t disagree with is within the system of rules at play and isn’t corrupt even if it is morally wrong.
https://in.news.yahoo.com/xi-jinping-undertakes-fresh-round-...
Another thing that doesn't inspire much confidence is looking at Hong Kong. The people there have unambiguously and collectively spoken about their desire to live under this system, often at grave personal risk.
Of course in an ideal world we wouldn't need a benevolent dictator at all, so, maybe a benevolent dictatorship is never the "best", but, at best, sometimes better than the worst.