I don't know anyone who gets married so that they can genetically engineer a "perfect child" like you are suggesting. Neither do I paint an entire culture with the idea that everyone hates themselves.
In a small immigrant community surrounded by attitudes and stereotypes, you tend to hang out with people like yourself with the same experiences and sense of humor thus creating a "Korean American Society" or other similar association. The children that are raised together because of their parents' friendships often see each other as family rather than as a possible date. So often times, they will look elsewhere and that means dating outside of your culture.
It sounds like you are seeing inter-racial dating as some kind of conspiracy. Let me reassure you that it is not. I assumed I'd be marrying Korean. When the time came to start thinking romantically, all I could see for Korean dating prospects is my "oppa" (big brother, son of my mother's friend). Ew!
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