Ive never been able to locate it, but I recall a column by Thomas Sowell - from the 1980s I believe, titled: VISIGOTHS IN TWEED foretelling theonswt of PC tyranny. It was the first of hundreds upon hundreds of his columns Ive read.
Are you sure it was Sowell? Dinesh D’Souza wrote an article with that very title in the early ‘90s.
I remember when Marilyn Vos Savant wrote an article in Parade magazine about PC. She thought it was one thing to be sensitive to others beliefs and feelings but she also said it was asinine to actually believe this crap. (OK, I probably paraphrased it a little.)