If you read “Art of the deal” and the most important part of the book, the publishing date - it becomes clear that the harsh, brash and ruthless method to NYC business was actually spawned from his figurative loins.
Before that book, NYC operated like most cities and fostered the same kind of people that the rest of the US does. His book laid out how he made a personal success by being a foaming-at-the-mouth animal where people are easily pushed over. It’s not fair, but it’s the reality to his brand of success.
So for him to make his way in this environment is second nature. Because he practically invented this environment.
You mean a corrupt bunch of insiders who stay close to their friends in city hall - "honest graft" as Plunkitt of Tamany Hall called it. You know, the Bush family kind of corruption where we are all very nice to each other so long as palms get greased and backs get scratched and the country is run to ruin.