Iron law of oligarchy is a term worth mentioning when you look at modern states like Russia or Iran, but when it was first mentioned by Robert Michels in 1911 modern democracies didn't yet exist.

Also Michels joined the fascist party as he believed it was the next step of evolution for human societies.

I urge you to read "why nations fail" by James Robinson and Darin Acemoglu to understand virtuous and vicious cycles in modern democracies and dictatorships and how it all works and interacts together.