The obvious solution is that lenders, including the DOE, need to examine the risk of the loan before offering it. By that I mean the major should be taken into account. Loaning someone $50,000 for a theater degree is not a responsible thing to do with taxpayer dollars.
In the private sector libs sometimes call this predatory lending, because the poor slob isn't expected to assess their ability to repay, only their ability to qualify, when they decide if taking out a loan is a good idea. Then the bank gets the blame when their eBay business doesn't pay the bills anymore.
So why is no one blaming the government for huge amounts of available credit for investment in poor career plans? Why are they subsidizing aka encouraging this?