https://fee.org/articles/student-loan-subsidies-cause-almost...
http://www.theatlantic.com/education/archive/2015/05/the-rea...
http://www.forbes.com/sites/timworstall/2015/08/03/increased...
I agree that land use decisions are also an important contributor to the problems in the mortgage market, especially in places like the peninsula. But without federal loan support, the market could not have reached the heights that is has since ultimately people can only afford to pay so much per month. If interest rates are much lower, then you can afford a higher principle amount for the same monthly payment. In a housing market with shortages, this allows prices to be bid higher.
But of course those land use policies are also exactly the kind of first-order thinking about government policy that I decried in my post above.