I would phrase it a bit different.and for fake boobs, its not only in porn but in modern culture, most females in most asian countries feel doesn't need to upgrade their boobs, what they want is to change their face (nose, lip, chick, eye lit, ecc)
(1) both Eastern and Western show biz (both mainstream and porn) embrace surgeries. But a Hollywood star would go for somewhat more naturalistic surgeries vs. Sillicone Valley porn stars would go for outrageous looks like watermelon boobs that screams whore/porn right away. So... gorgeous vs. slutty, the type and degree of surgeries is hugely different between mainstream show biz and porn. For Japan, there's much less difference between AV idol surgery vs. mainstream idol surgery. Of course AV idol tends to do more boob jobs.
(2) I don't think Asian men and women are less obsessed about boob size, B-cups are rarely consider as "enough". Put a D-cup next to a B-cup, D-cup wins 9 times out of 10. But If you put a fake D-cup next to a real B-cup, I think there's a big difference between East and West. In West, big tits win, no matter how fake. In East, fake boobs carries a price so a fake D vs. real B is more like 60-40 in favor of real. The big difference is how obvious the fake, if the surgery is obvious, a fake D-cups lose even to real A-cups, 10 times out of 10.
Nowadays it almost seem that the real busty idols like Julia, Hitomi, Anri Okita seem quite convincing as 100% natural tits. But the mid-range and even large-petite boobs (C- to E-cups) that often give me doubts.