To think that NY has been the most populated state for most of American history, and now a mere 4th behind Florida, Texas, and California.
To a large extent, New York can thank our inability to annex Canada for that. To a large extent New York benefited from being the most convenient U.S. Atlantic port for the Great Lakes states to make use of. But had Canada been part of the U.S. from the beginning, or even from 1812 onwards, Montreal would have taken over a good bit of that commerce. New York's decline is not due solely to the deindustrialization of the Rust Belt, but also due to improved transportation that has made New York City less of a chokepoint that it once was.