Uneven wealth distribution
It seems to me that even relatively poor cities in Asia are all getting a supertall (300 meter +) skyscraper, not because they have figured out how to make an affordable skyscraper, but because the elite controls a lot of money. They need specialized places to live, stay, and do business even if most of the people are riding bicycles.
Europe, which is wealthy, seems to have little interest in skyscrapers. There is not a need for a single complex in the city to announce that you are wealthy. Greece has not built a tall building in decades.
It does strike me as odd that Japan does not build over 300 meters. I suppose it can all be blamed on earthquakes, but when it comes to proposed superstructures, the Japanese seem to have the most fertile imaginations. Given their sophistication in building earthquake resistant buildings under 300 meters, I think they are capable of building higher even in an earthquake zone.