Yes, the notion that "most Americans recognize that for all intents and purposes, New York City isn't even really part of the United States anymore" is nonsense. The argument that NYC has capitulated on issues that Americans consider very important (save for money I suspect) could apply to most metropolitan cities (LA, Chicago, Houston,...). And, if so, those cities are also no longer part of the United States, which is nonsense. You may not like these cities but they are very much a part of this country and are worth fighting to keep.