The city's skyrocketing immigrant population and tight housing supply are forcing tens of thousands of New Yorkers to cram into illegal apartments.... Thank you, NYC "rent control" which insures both scarce, and run down, housing.
(By the by, what on earth is an "illegal" apartment? One that's cause in the city w/o a visa?"
Actually, rent control mainly subsidizes the middle and upper middle class. Rents outside Manhattan are generally at market.