I didn’t see any anti-Semitism in his remarks although clearly I thought they were inappropriate and not helpful to his election prospects.
I can’t speak for the other boroughs but Manhattan still has a large percentage of Jews. They really define the culture - in a good way, generally.
The only people who care about insults to New York are people who live in New York, which is NOT the center of the universe. The demographics of four of the five boroughs and much of the suburbs are way stacked against anyone even slightly right wing winning.