As I read it, that proposes it's undesirable because there are few economic benefits for moving.
That would suggest that people are willing to move if there were stronger economic reasons, but the economic disparity across the US isn't high enough.
While the OP suggests that people aren't willing to move despite there being an economic disparity.
Thus, doesn't your link support the thesis the STEM shortage is a myth?
http://www.washingtonpost.com/blogs/wonkblog/wp/2013/05/11/w...
Uprooting one's life becomes more undesirable.