In New York owning a car is a huge luxury, the city is giving away free real estate to the richest of the rich New Yorkers. Getting rid of free street parking is a great idea.
True, we should be careful to not conflate "Manhattan" with "New York City".
That said, I agree with OP's comment within the context of Manhattan. Anyone who owns a car there is very wealthy, even within the context of a wealthy city.
(I don't agree with pegging the divide at 110th street, that's much too low.)
Yes, the “parking is free real estate for the wealthy” idea is really a manhattan thing, but those numbers aren’t doing you any favors - that’s far and away the lowest proportion of car ownership in the country.
Charging is not going to fix that problem. If anything, the closer you get to charging market rates, the less accessible it becomes to anyone other than the richest of the rich. At least with free parking all vehicle owners are on an equal footing regardless of how much disposable income they have.
Not that I'm advocating free parking. I'm not. But this isn't a good argument against it.