He makes some good points about changing cultural practices and ideas that partially shape our vision of artistic golden ages as golden and how those practices and ideas blind us to the richness of our own age. But he's all too willing to wash his hands of modern composers who are increasingly exiled from both the classical and mainstream community, for example. He regrets it, and then just says, that's capitalism too. It's pretty easy to praise capitalism when capitalism is some weird omnipotent and perfect god. If you don't like capitalism (or a certain expression of capitalism), you just don't understand the Invisible Hand's ultimate design.
And then too, Cowen's approach to people and psychology seems hilarious. I seem to recall him admitting he possesses a somewhat autistic view of how people tick and that seems borne out in the book. Take this howler:
"Kurt Cobain of Nirvana committed suicide after only four albums, secure in his expectations of artistic immortality" (147).
That seems like a pretty fundamental misunderstanding of Cobain's emotional state and his feelings about his popularity. Or a misunderstanding of depression in general.
Or this, from a section entitled, "The Musical Revolution in Africa":
"Slavery was a disaster for its victims, but it revolutionized world music." (155)
And I know it is easy to take quotes out of context and make them seem ridiculous, but the paragraph weirdly equates slavery with some kind of "cultural interchange" and that the "barbaric form" of slave-based "cultural contact" paved the way for "later, more beneficial voluntary contacts". Cowen's not trying to be offensive, but he's refusing to grapple with the serious moral issue at stake here. He's even ignoring the fact that pro-capitalist economists were one of the first groups to see the problems with slavery.
It's like something Monty Python or Mr. Show would put in the mouth of a well-meaning buffoon.