One of the changes that happens in language is how you refer to people groups. This isn't a matter of being politically correct; it is a matter of being sensitive and not unnecessarily offensive.
Identify a person primarily (or at least initially) by their ethnicity can give the impression of relational conflict and even hostility when it may not be intended. Imagine a British person seeing an Irish person he doesn't know, and saying, "Hey Irish." Or a white person saying, "Hey African." Or a European seeing a tourist from New York and saying, "American."
A good example of this is in John 3:25. Jesus (and his disciples) and John were baptizing, and the Gospel records that "a dispute arose between John's disciples and a Jew (Ἰουδαίου) about purification" (CSB, also NASB, ESV, NRSV). Translating the anarthrous Ἰουδαίου as "a Jew," given the history of anti-semitism throughout the world, is probably not the best choice. (The KJV accepts the variant plural reading, "Jews.")
Other translations try to not make the same mistake by translating "a certain Jew" (NIV, NET, NLT). "Certain" is their attempt to render the anarthrous Ἰουδαίου and avoid any sense of being pejorative.
But to my ears, "certain" introduces a foreign concept — that there was something special about this one particular Jewish person. He was not just "a" person but a "certain" person, a "specific" person. That is certainly not John's intention.
This is part of the challenge of translation. Words carry so many slightly different nuances to different people, and it is common for one person to hear something that others don't hear.
I would prefer "a Jewish person." There is no stereotyping, and it translates the anarthrous construction better.
By the way, this is somewhat similar to addressing people with disabilities. While older translations may refer to the "lame," in today's polite and sensitive speech you would never lead with the description of the disability, as if the disability defines the person. He or she is a person who is unable to walk. This isn't being politically correct; it is being polite and sensitive.
