“I don't think it happens in countries governed by autocracies, because the economic elites have much more trouble overcoming the control and dominance of the political elites”

Are you kidding? The whole point of Putin-style oligarchic kleptocracy is to fuse the economic and political elites into one ruling class. A Putin or Muhammad bin Salman (or wannabe Trump) holds both the economic and political reins, and uses one to dole out favors and punishments to the other. Autocracy is precisely where today’s inordinate concentration of wealth leads.