Why are SO MANY asian actresses prudish?

I'm not talking about B movie actresses who do slutty crass movies or porn actresses. Focusing my question on legitimate actresses with name recognition. Is this an asian thing? If you look at like the last 4-5 Oscar winners for Best Actress they all did scenes of various nudity in the film for which they won! At the very least they had a topless scene. I can't think of a single mainstream prominent asian actress in modern times who does a serious dramatic role in a major motion picture where topless or something is done. I don't think Grace Park would ever take on such a role either. And the stuff she did in BSG doesn't really qualify since everything is shot from concealing angles, with objects conveniently in the way, etc. You don't see this same phenomenon with major white, hispanic or black actresses. I can't think of an A list American actress who hasn't done at least a topless scene in her career, but time after time virtually every serious asian actress I've come across has gone their ENTIRE CAREER without so much as a single topless scene. Same thing applies to asian top models too like Lin Chi Ling in Taiwan. Virtually all US supermodels have done at least topless shoots, but this is still taboo in China/Korea at least. Weird.

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