I did some researching about this Argentinian celebrity city and found out that people in the 1800s wanted to model it off of Paris, another big city that you might have heard of (bonus point if you know which country it's in! Hint: Baguettes and croissants.). Because of that, some neighborhoods make you feel like what it might be like to be in a European city, mostly where wealthier people live. Other neighborhoods are home to artists, who call attention to societal problems and who often don't have as much money as many of the other inhabitants.
Buenos Aires survives, then, due to the constant tension between its historical paths (literally) paved by the elites and the routes blazed by its rebels.
What can harm Buenos Aires? Well, anything that harms any of today's cities. I'm mostly thinking of global warming and overpopulation!