Many people still don't understand the details about Eileen Gu's nationality.

If one of the parents was a Chinese citizen and not a permanent resident (green card/permanent residence) when the child was born, then the child has Chinese nationality. For example, if the parent was traveling, studying abroad, or working abroad.
At the same time, the child may have acquired foreign nationality, but the Chinese government still considers the child a Chinese citizen and does not recognize their foreign nationality.
In other words: the child can have de facto dual nationality, but the Chinese government does not recognize the foreign nationality. However, the country of the child's other nationality—such as the United States—may recognize both the child's Chinese and American nationalities.
If Gu Ailing's mother had not yet obtained U.S. permanent residency when she gave birth, only holding a work, study, or tourist visa, then there is no issue with her Chinese nationality.
Conversely, if Gu Ailing's mother had already obtained U.S. permanent residency or U.S. citizenship at that time, it would be a violation of Chinese nationality law.
That would be a typical case of illegal behavior being overlooked, which, from the perspective of the Party-state, can be seen as a special case handled differently—after all, it is governed by law under the Party's leadership.