It's a good article. The stuff about people overusing credit cards is completely true. As the article says, each adult has about 4-5 credit cards. The number among some young women is much higher. You'll see them sliding close to a dozen credit cards out of their wallets at times, trying to recall which one they can use and which one they can't!
The article keeps calling Gangnam a neighborhood! It's not! A dong is a neighborhood and there is a Gangnam-dong but a gu is a district and the song is about the district. Gangnam-dong is probably the most commercial part of Gangnam-gu and it's arguably the most famous dong in all of Korea but other parts of Gangnam-gu like Apgujeong and Cheongdam typify "Gangnam" a little more (especially some of the things the article mentions) It's so true about people skimping on the essentials to afford luxuries and coffee shops are EVERYWHERE in Korea! There were about 5 Tom N Tom's coffee shops, 2 or 3 Starbucks, Café Java and a couple of Café Benes withing walking distance of my apt and those were just the ones I can remember and also just ones that were part of chains. Coffee shops are places to hangout 1) because apartments are too small to welcome visitors very often 2) because they are seen as somewhat trendy because of how popular they are made out to be in American movies and tv programs.
It's also true that people in Gangnam tend to be trust fund kids rather than self-made millionaires but the Korea's true elite still see Gangnam as a "new money" area.
I'm not sure if Psy's video is intended to be satirical or subversive. Most Koreans can't even grasp the concept of sarcasm, let alone satire! Also, one look at a Korean variety show will give you a sense of how infantile and straaaanggee Korean sense of humour is...
For example: Choco Boy - "That's Very Hot"
I suppose this was subversive in a way since these performers were clearly trying to get Koreans to be more gay-friendly or more comfortable with "camp" but if Koreans really knew what this act was intended to be they (as a society) would not like it ONE BIT. This was a family show. Some of my really young students used to do that little grind/dance and say "that's very hot" and I was always like, "please stop...please."