I don't know about other East Asian countries, but in China's case it is indeed has to do with government's policy.
No one "naturally" look up to or look down upon any ethnic groups, it's all aquired taste. Our perception towards others are influenced by media, if the media portary the West as some kind of sacred place and Western people are superior creature, surely they will be looked up to. In China media is controlled by the government, it is apparently government's fault to let the media glorify the West.
Culture invasion is another issue, when people watched too much hollywood movies, they got brainwashed by western aesthetic standards.