Not sure if you read Derek Webb's article, but he makes the case that piracy is better for musician's than Spotify, because with Spotify people have paid for it so the artist never stands a chance of making significant money from a fan, whereas with piracy the will have the internal understanding that they haven't really given anything to the artist, and eventually they may decide to buy an album.
As easy as it is to hate the big bad RIAA, it's a red herring. Musicians are under no obligation to support any particular business model. And contrary to what you say, if every musician puts their music on Spotify, then Spotify becomes the obvious consumer choice, and that sets a maximum value that music is worth, and that value is orders of magnitude less than it can be worth under the iTunes model. Musicians don't have to put their music into Spotify though, and as long as significant numbers of them don't then the higher value market for music can still exist. Piracy is definitely inevitable, and I believe it's a waste of time to try to fight it at the individual scale, but there is no reason artists have to bend over and accept a fraction-of-a-penny pay-per-stream model as inevitable.
You're ignoring the long tail of streaming. Streaming revenue will continue bubbling in, while sales are shortlived. In many cases streaming revenue will surpass sales within a year or two.
As easy as it is to hate the big bad RIAA, it's a red herring. Musicians are under no obligation to support any particular business model. And contrary to what you say, if every musician puts their music on Spotify, then Spotify becomes the obvious consumer choice, and that sets a maximum value that music is worth, and that value is orders of magnitude less than it can be worth under the iTunes model. Musicians don't have to put their music into Spotify though, and as long as significant numbers of them don't then the higher value market for music can still exist. Piracy is definitely inevitable, and I believe it's a waste of time to try to fight it at the individual scale, but there is no reason artists have to bend over and accept a fraction-of-a-penny pay-per-stream model as inevitable.