There is risk in cash, it is called inflation, if you bought a car last year you lost 7% + depreciation of the car since you bought it. The SP500 is up 11% since last year.

This means you would have lost 7% to inflation, 11% to potential upside plus depreciation of your car. Assuming your car did not depreciate because of current car production shortages you lost 18% of your money buying cash vs 3%-4% interest on the loan.

Cash is not risk free