Foreign investment for money laundering and land banking is NOT unique to NYC. I first learned of it in the early 2000s reading about rich neighborhoods of London that had been hollowed out by Saudi and Russian kleptocrats buying buildings that they lived in for a month or so a year and killing all the business in the neighborhood as they depopulated it.
Then I read about Chinese billionaires and millionaires buying up land in Wellesley and Newton and other Boston suburbs, doing the same thing. There is one Chinese billionaire who has bought a significant portion of Harvard Square and Cambridge, MA and is just banking the real estate, for what purpose nobody seems to know.
One of the things that may, just may come out of the Mueller investigation is the criminal history of Trmp’s real estate deals which go back to the 1970s and have been consistently associated with cash transactions for money laundering purposes. I suspect that much of the high end real estate business is about money laundering. Driving up housing costs and destroying neighborhoods is simply an additional “benefit” for the kleptocratic kakistocracy.