Showtime's 'Roadies' piles on the pain, but where's the passion for rock 'n' roll?

The music-industry drama, just recently so youthful and full of promise, is now on life support: HBO’s “Vinyl” bombed so hard it contributed to a network shakeup, ABC canceled “Nashville” (subsequently rescued by CMT), and even Fox’s “Empire” had a rocky sophomore year.

A hero was obviously required,...