I think that the crucial word in the quote might be "article". What works of visual art have in common, whether they are a painting by Monet or a bejeweled skull by Damian Hirst, is that they are articles: objects. You can buy them and take them home (if you have sufficient funds). If you pay 23.7 million pounds for "Le Grand Canal" by Monet, then you have something worth 23.7 million pounds hanging on your wall. It is a beautiful article, yes, and an expensive one, but it is your beautiful article.
That was painted in 1908. What is the value of a piece of music from that same year in economic terms? Perhaps the most important classical work from 1908 is Arnold Schoenberg's String Quartet No. 2 in F# minor, op. 10. The last movement is historic because it is Schoenberg's first venture into atonality:
The economic value of this piece of music is pretty tiny--in fact, performances of it are rare. True, it is an experimental work, but so was the painting by Monet. What is the difference? I think it goes back to the Veblen quote: "a beautiful article which is not expensive is accounted not beautiful." Now the Monet was probably not expensive when it was painted, but due to a century of appreciation by art critics, the Impressionists have become greatly renowned and their paintings highly valued. I think it is the confluence of two things that cause this phenomenon: critical admiration and the physicality of the object. You can BUY a Monet and take it home and hang it on your wall. It is an investment that speaks to both your wealth AND your taste. Somehow it also reflects on your moral qualities as well. It's a win-win-win!
But the Schoenberg, or any other piece of modernist music, cannot be bought, cannot be owned by a collector. Some music manuscripts such as pieces by Mozart, or letters by Beethoven, for example, can have value and be sold at auction, but the amounts are trivial by comparison. And, of course, these manuscripts are not the music. The music is what you hear in the concert hall or in your listening room at home. The score is not the music (though it is like a recipe for assembling the performance), it is the performance that is the music. And you can't own it in any other sense than either experiencing it as a listener or as a player. All you can own is a ticket to the concert or a recording of a performance. I own a box of orchestral music by Bartók conducted by Pierre Boulez. Excellent performances. Cost me about $40.
To speak as a philosopher, the ontological status of a piece of music means it cannot be an article or object in the way an Impressionist painting can. Therefore it cannot be owned or possessed. Therefore it cannot be a salable commodity. Therefore it cannot have great economic value. What it can have is great experiential value, but this can be purchased, either in the form of a ticket to the concert or a recording, for less than a hundred dollars. On the other hand, the Monet just hangs there and does not have the experiential punch that listening to the last movement of the Bartók Piano Concerto No. 2 has:
Try to slap that on a square of canvas!
Still, the problem is that this experience is not a uniquely tradable object. There can be lots of concerts of it and lots of copies of recordings of it. What makes the Monet ostensibly worth 23.7 million pounds is that there is only one.
It's a problem...