The upside could be life-changing, if sized appropriately, the downside could be the equivalent to a bad day in the markets. Couple that with the fact that this hedge is both uncorrelated to nearly everything else, and at the same time it lacks the term risk of most hedges, bitcoin doesnt decay like options, or credit derivatives.
Demand for borrowing in the DeFi world comes as a result of either margin trading on decentralized exchanges or from borrowing on DeFi applications. The constant fluctuation of demand and supply on DeFi applications results in yields that are fairly volatile