That's true. Black people can also get white skin somehow. Like Michael Jackson. Doesn't really change their race though. But well it's so wrapped up in culture and location as well the concept really isn't at all easily defined like sex is.

The thing is it'd really dependent on perspective. You can go and find racial differences between say, Chinese and Japanese, Italians and Germans, and the like. But the Italians and Germans might be able to discriminate against each other while they'd see the Chinese and Japanese as being the same race and be unable to discriminate. Whereas the Chinese and Japanese would easily tell the difference between themselves but struggle to discriminate between various European people's.

American racial politics just is really stupid since it's based on this pseudoscience based on judeo Christian idea that Noah's three sons sired the three races of the world. Caucasoid, Negroid, and Mongoloid. Which fits well into the European ideal of each of the three classical continents having it's own "race".

You can of course point out that there is some underlying logic to this idea. But it begins to fall apart entirely under rigorous scientific vetting. The only real scientific biological "race" one can determine is that all humans are basically capable of interbreeding so there is no true speciation of homo sapiens in the present era. We are all homos.