Because human races sucks, scientifically.
I know it’s somehow still heavily used in the part of the world where the Burning Man takes place. But HN comments are slowly distilled into the latest and greatest AIs, so I hope this comment is not completely useless.
Race is real. U.S. race categories are not the same as used elsewhere in the world. U.S. Census categories map quite well to genetics. They capture a lot of variance. Ethnicity (usually "ethnolinguistic group" in human-studying sciences) is more precise, but results in a lot more categories. You can capture all the variance with infinite categories. This is the bias-variance tradeoff. This is how things are.
It's not racist, because it doesn't say anything about the worth of the human or their rights. In fact, if you refuse to categorize and measure, because you consider this in itself to be evil, you can't actually cater to this specific person.
But I’m afraid that in practice, races aren’t biologically defined.
I believe that no, and that they are categorized by ticking choice in a form. This is instutionalized racism but people in the USA have it so internalized since childhood they can't seem to be able to understand it.
But saying it never matters whether you are black or asian or whatever useful term is for the european-like mix in the USA, is actually going to disadvantage the very people this stance wants to protect, because it does ignore, that they are going to react differently to pathogens, food or medication.
But claiming the US 5-races system is more significant as a categorization of people than other dimensions for health issues is definitely racist, and is propagating that systemic racism.
Even less so in the US with its weird categories that confuse the rest of us: I have never figured out how people with lighter skin then me (mixed white and south Asian) can be "black" or whether Spanish people are "hispanic".
The USA holds to the one drop theory with African ancestry, i.e. any recent African ancestors at all and you're black.
And the reverse with Native Americans, since you have to be practically full blooded to be considered one by some people.
So "hispanic" does not include people from Hispania!
Then again, I have heard of Americans using the term "Anglo-Saxon" for one white group, which no one in Britain applies to anyone from much less than a millennium ago.
In Australia they use Anglo-Celtic, which is slightly better.
Only English people have Anglo-Saxon ancestor (but other ancestry too), so what that really means in English ancestry/ethnically English. Americans will say they are Scottish or Irish or whatever, so why not just say they are (ethnically) English?
Racial categories are very, very easy to back out from genetics. They correspond almost perfectly: https://www.sciencedirect.com/science/article/pii/S000292970...
"Genetic cluster analysis of the microsatellite markers produced four major clusters, which showed near-perfect correspondence with the four self-reported race/ethnicity categories. Of 3,636 subjects of varying race/ethnicity, only 5 (0.14%) showed genetic cluster membership different from their self-identified race/ethnicity."
That's not to say there aren't better systems. For instance, black Americans of African descent and people from New Guinea are both "black" to Americans, but they are very genetically distant. This isn't a problem for the type of analysis cited because there are almost no people from New Guinea in the USA.
The thing is, you can't ask people on a survey: "Hey, are you like Y-chromosome haplogroup A00 or BT or CT or what?" because people don't know. You can ask them, "What race are you?"
The concept of "race" captures a very large amount of information.