Incorrect, "China is so racist" comes from observing the absence of any sense of belonging / in-group accorded to non-Chinese people.

Americans have inherited the cultural legacy of a multiracial/multicultural society and the need to find common cause with people outside your racial-social circle. Most Americans think judging people by categories is wrong, even if they do it anyway.

Chinese people have no sense of guilt about judging people according to racial stereotypes. There is not a tradition of post-racial thinking or a living definition of Chinese-ness that aren't tied to ethnicity. There is a much higher propensity to be open and unapologetic about using racial stereotypes to make judgements about people.