The use of "oligarchy"is a ~3,000 year old mistake commenced by Aristotle (Wikipedia: "oligarchy"), but it is still in use by a lot of people in the alternate media who contemplate the structures of our "economy."
As the video at the bottom of this post shows, Chris Hedges uses the word "oligarchy" tens of times, as Aristotle was wont to do, in order to describe what is technically a plutocracy (Wikipedia, Oligarchy), not an oligarchy.
The improper use of the term, however, does no damage to his understanding of the Ferengi system (Life In The Ferengi Home World - 3) he is describing.
Truth be known, the economic system is complex, so, analyzing it is somewhat akin to the ancient story of the blind men describing an elephant.
The economic system looks and feels a bit different, depending on the part of it which one uses for an analysis.
For example, I have used the terms "plutocracy", "plutonomy", "wartocracy", "military-oil-media-complex", and "American Feudalism" to describe "it."
IMO, the main thing, in any valid analysis of "it," is to determine what is being done, in terms of doing the common good v. doing the common bad (The Common Good, 2, 3, 4, 5, 6, 7, 8, 9).
The previous post in this series is here.
Interview of Chris Hedges:
Interview of John Perkins (reformed economic hitman) ...