(Aside: This “no equivalent in U.S.” trope is really overused, and in this instance, the comparison is clearly hyperbolic and incorrect. Gangnam is obviously not a Silicon Valley, since there is no huge concentration of tech companies in Gangnam. Nor is it Wall Street — that would be Gwanghwamun / City Hall area, north of the river, where all the major banks have their headquarters. Gangnam is not Upper East Side either, since Gangnam is decidedly nouveau riche. The old money of the kind that occupies the Upper East Side of New York is found in Yeonhee-dong of Seoul, north of the river. The Miami Beach comparison is too dumb to address.)
One more post about the song because this post is too good (and informative) not to link to.