Following up on my earlier point, we don't really value the same things today that made Paris in the 20s seem so cool. There are great cities to see paintings and sculptures and modern art: Paris, Rome, Prague, Krakow, etc. There are cities with thriving theater: Paris, New York, St. Petersburg, London, Seville. There are cities with world-class, cutting edge food: Paris, Tokyo, New York, Copenhagen. There are multicultural cities with progressive local leaders and stable, thriving local economies: Paris, London, New York.
I think the answer you may be looking for is Paris.