If the 1960s were all about The Beatles, the ’70s were more of an open playing field, with rock ‘n’ roll splitting into ever-tighter niches. The heady era brought us stars of glam rock, heavy metal, krautrock, prog rock, and punk. Alongside solo stars like David Bowie and Elton John, Led Zeppelin and The Rolling Stones seemed most apt to usurp The Beatles’ throne. Formed from the dying embers of The Yardbirds, the band that gestated the talents…