Interesting you would call Taiwan developing world, it is one of the most developed countries in the world--21st out of 188 according to the UN.

Source: http://focustaiwan.tw/news/asoc/201409180039.aspx

As others have said you are actually describing class and cultural differences which don't depend on country. I moved from the Midwest to LA and am still in shock and awe at the displays of wealth here. I grew up with a much more frugal mindset and in a place with much more modest homes. Keep in mind even in the US, the fraction of people living in Bel-Aire mansions, or anything even close to that wealth, is very, very small.

Also, I suspect that there are plenty of very wealthy people and luxurious residences in Taiwan that would be equally jarring to you. My point is it's not the country, it's class and culture.