Staged to celebrate the completion of the Panama Canal, and drawing over 19 million visitors in only nine months, the Pan-Pacific International Expo rose like a literal jewel from the ashes of San Francisco's 1906 Earthquake and Fire.
A Century of Progress International Exposition was held in Chicago, Illinois from 1933 to 1934 to celebrate the city's centennial. The theme of the fair was technological innovation. Its motto was "Science Finds, Industry Applies, Man Conforms".
The 1939-40 New York World's Fair, located on the current site of Flushing Meadows-Corona Park, was one of the largest world's fairs of all time. The fair ran for two seasons and over 44 million people attended.
The Golden Gate International Exposition was held in San Francisco, California to celebrate the opening of the San Francisco-Oakland Bay Bridge and the Golden Gate Bridge. The exposition's first season ran from February 18, 1939 through October 29, 1939 and its second season was from May 25, 1940 through September 29, 1940.
The 1964/1965 New York World’s Fair, located on the current site of Flushing Meadows-Corona Park. The fair ran for two seasons and took place without sanctioning from the Bureau of International Expositions.
Expo 67 was held in Montreal, Quebec, Canada from April 27 to October 29, 1967. It was considered to be the most successful World's Fair of the 20th century, with over 50 million visitors and 62 nations participating.
The only real model lifelong New Yorkers had for a large size urban park, was Central Park. I suspect they viewed Central Park as the gold standard because that's all they knew. And as far as I know, the large ponds in Central Park never had fireworks show capability.... in fact such a thing was viewed as gaudy and distasteful. They liked their Central Park ducks and comparitive quiet respite from Manhattan noise and air pollution.
I also understand that there is quite a disdain by big money Manhattanites and the City Hall they control, for Queens in particular and Long Island as a whole. They viewed the entire area as uncouth Archie Bunker and Ralph Kramden / Ed Norton types, who did not deserve any investment in a top notch urban park, which they reserved for themselves in Central Park.
Say what you will about Robert Moses, but he saw things differently and wanted to invest in making life better for Queens / LI residents, like Jones Beach and FMCP.
By the way, IMHO, Central Park is nice but isn't (and never has been) a gold standard. They really needed to look MUCH farther afield to find examples of 'the best of the best'. For instance I look at Chicago for a superb example of an urban fountain (Buckingham Fountain).
Seattle has some great parks too, and Vancouver, Canada has one of the very best (Stanley Park).