Corporations finance part of their borrowings through bonds. These bonds need to be paid in full + the interest when the bond matures. Corporations and banks typically repay some of these from cash, and some by issuing new bonds.
Right now no one is getting to issue new bonds at all. Banks cannot lend because the risk rating on these bonds has gone up, meaning they in-fact need to sell said bonds to reduce their risk exposure.
Thus the FED is acting as a lender of last resort directly to major corporations. Without this last resort said corporations would need to either fire-sale off assets to pay the principle on these bonds or face a technical default.
Covenants on their other bonds mean that if the corporation defaults on any of their bonds, all of the bonds become callable. It is 110% not good to have any major corporation go into a technical default. We are talking about companies which have plenty of assets and strong businesses.
Thus the Fed and US Government are/should be acting to avoid any such rapid deleverage. It took Japan 2 decades to reduce leverage in the corporations. Without intervention the US could undergo this same deleveraging in a matter of months. It would throw the American people into such a deep poverty the likes of which we've not seen since the great depression.
Which is to say: these bailouts are going to happen. No one who understands what is at stack would choose to "let the house fall".