I actually bought his kindle book and with plans to explore every artist he covers. I don't care whether he likes the artist or not, however because he covers virtually every semi-important artist whether he likes them or not, you are not going to missed out anyone important exploring his book. He may hate various popular artist but he is not going to ignore them
Now I think his opinion are wrong and some of the objective facts underpinning his opinions are wrong however he doesn't get into "equality of styles/genre" of music.
He clearly prefers the idea of music being connected to avantgarde. His rating of his music is reflected of his very personal ideology of music and hence his reviews are essentially self-expressive art itself similar to George Starostin equally bias reviews.
I much prefer a reviewer who frames the entire musical repertoire on their own personal ideology rather than "judging music within it's own term" as I feel the latter is betraying your own personality and your own identity.