It is cheaper than most of New York (I am told, never lived there). But people like your son have raised the cost of living in that area from what it was.
So the people who were living there are having to adapt to the changes, and don’t like it.
Chicago has areas like that, and it has been a source of tension to some of the groups.
How did my son raise the cost of living there?
He was peddling stuff on the streets without a license and trying to sell his art, most households in Brooklyn had a lot more money than him.