Q. With the new rule for the en dash and personal names (CMOS 6.85), does that mean a city like Winston-Salem will be spelled with an en dash now?
A. That’s a good question, but the new rule does not extend to a place-name like Winston-Salem. Nor would it extend to a name like Merriam-Webster (the dictionary publisher). Such names are like the hyphenated surname Newton-John in the name Olivia Newton-John. Though each of those three names (of the city, the publisher, and the person) combines two names, they’re each considered to be a single hyphenated unit.
The en dash in a term like “Epstein–Barr virus” or “Ali–Frazier fight,” by contrast, is supposed to help clarify that something (as a virus or a fight) is being attributed to two people rather than just one. A Winston-Salem virus or Winston-Salem fight, on the other hand, would be a virus or a fight named for a single city in North Carolina—one that happens to have a double-barreled (and hyphenated) name.
Note, however, that the names of some places would get an en dash in Chicago style: for example, Minneapolis–Saint Paul, where the dash connects to an open compound (see also CMOS 6.86).