I completely disagree with that premise. It was true until about 1967, but not after that. Though I always got the sense that he thought most things other than Springsteen sucked after 1967.
But you also can't have the reverse (which is what most orthodox rock histories lean on): that the story is only told through albums. It conveniently marginalizes artists of color, women, and those with a backwoods upbringing - because those artists didn't have control over their content and weren't allowed to make albums to support their visions for many years after Boomer white rockers were. That's what Marsh was trying to say.
I'll agree that he swung the pendulum too far the other way, but Jann Wenner and his ilk had put the pendulum in the wrong place from the get-go.
Marsh also has many songs in the book (written in the late '80s) from the '70s & '80s. His update in the late '90s doesn't change the list, but it has a list of of songs in the new preface from that decade he'd include (I think it was like 100 or so, including many that the demographic on this board would agree with).
I'm not defending him in any way except to say that what we were told was important for several decades leaves out a ton of music because it wasn't made from 1967 to 1979 by guitar bands who had a freedom of expression other artists didn't have. That doesn't make the music those ignored artists made any less vital to the story.
How do girl groups and Brill Building records, in Rolling Stones' R&R History (and every other tome they #### out), get less word count than the ####### Airplane when that music influenced everyone from the Beatles to the Ramones to Springsteen to Prince to Madonna? Marvin Gaye gets one paragraph (along with the rest of the Motown artists outside of Stevie Wonder, who got tokened in with a page or so full of backhanded compliments) when the Doors get pages? Johnny Cash gets barely a mention for his time at Sun in the '50s (& none afterwards) and Willie Nelson scrapes a paragraph (only for his concerts and ignoring his recorded output, because: Woodstock!) while the (mostly awful) Haight bands get an entire article to themselves.
I get that Marsh is a jerk and tries to provoke - trust me, I've read more of his crap than is healthy for anyone with a working mind and I know his game. That doesn't mean he's wrong, though, just because you think he doesn't like Neil Young (I've heard him wax poetic over Bowie on his radio show, who he trashes in this book way more than he does Young).
If I were doing this ranking, I'd have in some of the artists he leaves out. Off the top of my head, I'd have one Floyd, a couple of Young's, two Purples, maybe a half dozen classic prog songs, and 2 or 3 Bowies. I'd boot the Roxy Music songs he included, though, because they do nothing for me. I don't think he had any Santana, which I would also include.