Music in the form of a physical or digital copy of a recorded track is not rare. Album pricing is based on supply and demand. The latter has decreased significantly in the past decade. Short of pulling a Wu-Tang[1], it would be futile for artists to try to fight market forces.
If Swift really wants to discuss the value of music in the context of music as an important, rare art form, focusing on what consumers pay for physical and digital copies of recorded music makes about as much sense as valuing Monet's Water Lilies series based on how much Water Lilies posters sell for.
There are several rights associated with music and people have been buying and selling these rights for decades. Royalty Exchange[2] is an online marketplace for these transactions, and there are even focused funds[3] that essentially give investors the ability to treat these rights as an asset class.
Savvy artists focus first and foremost on ownership, not what consumers pay for a song or album.
[1] http://www.theatlantic.com/business/archive/2014/05/for-5-mi...