Isn't that the point? "Karen" is a pejorative term for an entitled white women, usually middle aged. The purpose in using the word "Karen" is to combine racist, middle aged, white and female and assign it all with one word. No, it's nothing like the N word, and it hasn't been used for centuries. It's not used to oppress white women. It IS used to dehumanize them. That seems to be the authors intention.