Sometimes I wonder if the mortgage model of buying houses will have to change or adapt in the future. To me it seems to be a lending model especially prone to a

Sometimes I wonder if the mortgage model of buying houses will have to change or adapt in the future. To me it seems to be a lending model especially prone to abuse because of the boom-bust cycles it creates: a bunch of people bite off more than they can chew when debt is cheap, and rationalize it with the assumption that housing prices will only increase, so they're not even losing money by taking on that huge debt responsibility. Then when interest rates go up or they lose their jobs, they become unable to support their debt, leading to massive foreclosures, creating a housing glut that erodes others' liquidity (simple supply vs. demand) and puts them underwater. Obviously this can happen to varying extents among other equity markets but lenders are much more likely to give someone a $400,000 loan to buy a house than to buy stock. I don't think this is necessarily sustainable.