I don't know why but likely changing diets and activity levels east asians (korea, japan and taiwan) are getting bigger breasts. Each country has a different body type but this combined with often hugely thick asses and legs make amazing bodies. Any stereotype you have about asian woman should probably be tossed. I daily encounter many woman taller than 5'10, and daily i run into women who have either two types of big tits: they have a healthy body weight and genetics is blessing them (chubby, but often with a much slimmer waist and arms than a comparable western woman) i've seen some g cups and bigger that i was 95% sure were natural.
Or the second type: the 20 to 35 year old obsessed with their appearance who ranges from anorexic to sub-healthy and may have medium to big implants. I see a lot or proportionally impressive dd to f cups and occasionally an artifical g, but they all seem made to look as realistic as possible.
The overall effect at its best is of well dressed women who have extremely thick and shapely legs and bum, a very skinny waist and large, heavy looking tits along with beautiful skin and faces. Everytime i step out the door i cant help but boobwatch all day