Uh, no it’s not. The Lower East Side, Little Italy and Chinatown are areas lived in mainly by low income people. They have had some gentrification but not a lot. Stuyvesant Town, a large series of high rises in that same area roughly has had rent controlled apartments for moderate income residents since the 1940s. Has its own high school, although parents can choose to send their children elsewhere. Many workers share apartments in Midtown in order to be able to live in Manhattan and be closer to work.
North of Central Park is Harlem. There has been a lot of gentrification in parts of Harlem but there still are lots of poor, working class and middle class people living there. There are high rises on Riverside Drive from 125th Street úntil it ends around the Cloisters and the majority are rent controlled. Almost entirely occupied by middle class residents. On the East River side, most of the high rises are public housing.
North of Harlem starting around 157th Street is Washington Heights which is not much different today than it was portrayed in the Lin Manuel Miranda movie. That runs over 40 blocks north where we get to the last neighborhood in Manhattan, Inwood. It was almost exclusively Irish when I lived in New York and had the second highest number of firemen and cops living there in the city. Staten Island was first. I’m sure it’s changed now but I’m equally sure no rich people live there.
I would say your assessment of only rich people living in Manhattan is off by 90%.
