"Euphemism treadmill" [1] is a real problem when medical terminology enters common circulation. Various medical terms have shifted into insult or slur territory over the years - a risky example being "mentally retarded". Note it started as a polite expression used in stead of earlier expressions that already fell victim to euphemism treadmill - and now is understood as an insult. "Handicapped" is an example that went from polite ersatz word to bordering on insulting in our lifetimes.

[1] https://en.wikipedia.org/wiki/Euphemism#Euphemism_treadmill

There's one species of humans still around. Race is a non-scientific category that got made up a few centuries ago, and has continually changed over that time. Ethnicity is the regional and cultural group of usually related people that everyone prior to western colonization understood as separate groups. Often you could assimilate into a different ethnicity.

So Romans would have understand themselves to be different from Greeks, Persians, Egyptians and Jews.

Maybe so. The point I think should stand however, pedantry or no because -

First, ethnicity (1) is very much not race (2). Second, and I assumed (wrongly, apparently) that a reader might follow this discussion to a logical end, which is to question why determining race using AI or any other means is even neccessary or remarkable. The article briefly knocks on that door in the last section (titled "so what"), but has nothing on offer.

If I'm simply redefining words then I'm marginalising years of racism. Mandela, MLK and many many more must similarly be pedants, no?

(1) https://en.wikipedia.org/wiki/Ethnic_group

(2) https://en.wikipedia.org/wiki/Race_(human_categorization)