Exodus citywide in NYC — but mostly from these zip codes

New York City’s population drain in 2020 occurred not only in wealthy Manhattan enclaves but in less well-off neighborhoods across the five boroughs, according to a new report by real-estate firm CBRE.  And although the market has begun to modestly rebound, experts say luring people back won’t be easy.  Among the most-walloped areas were high-revenue-generating…