I agree with Kyle Smith (and pretty much everyone) that the recent kerfuffle at Condé Nast, in which the white CEO’s black executive assistant was so insulted when her boss gave her a copy of The Elements of Style that she quit in protest, is ridiculous. But I must chime in to point out that the book is trash. It’s the worst kind of linguistic prescriptivism: The authors took a bunch of their own personal preferences and dressed them up as rules, making a hash of basic grammatical concepts in the process.
The linguist Geoffrey Pullum has been a relentless critic of the book over the years. His most enjoyable fusillade against the tome, “50 Years of Stupid Grammar Advice,” unfortunately sits behind a paywall, but you can see his more academic explanation of the many problems with the book, which is no less brutal, here.