You separate Sports from Politics, indicating you are still very idealized. Lang was a national heroine, and what she did is understandable because she is a secular human being, living on money made by herself, however is not easily accepted by most of Chinese people with Chinese nationality. How Americans can image if Micheal Jordon changed his nationality and helped China to defeat American team.
If Lang trained herself by hiring her private coach and earned her fames using her own money, becoming a national heroine.
I do not want to say much about what she has done. She was trained in the national bases and successfully won a lot of titles, which were used as her today's position and attitudes, in addition to the facts that she was asked for staying as a national coach before she joined American.
Anyone has his or her way to finish their lives. As a Chinese, you have to follow our tradition to translate your philosophy into actions: we follow common rules to expression our respects on our history, our culture, our traditions, our religions, our endeavors, our ethics and our hero(ine)s etc.
From what you say, I know what kind of person you are, and I respect what you think about, but I tell you not all people think the way like yours, that is, why my China is still bearing boundless prospects. Do not tell me Sports is nothing to do with countries. I respect your choices, but I always eulogize national heroes.