You're trivializing the issue. It's not just "inflating stock prices". Credit markets that are required for the basic functioning of the economy have completely frozen up.
Companies that are completely solvent can't meet short-term obligations because the commercial paper market has frozen. Money market funds, which are basically savings accounts, have fallen below par despite only containing short-term high-quality bonds that would never default in any reasonably scenario. Repo markets are forcing mortgage providers to de-leverage positions (which will in turn lead to foreclosures) based on the fact that there's no liquidity for the collateral. International trade for basic and necessary goods in the supply chain has grinder to a halt because banks are no longer extending trade finance.
Whether you like it or not our economy is completely dependent on having a well-functioning "money market", where short-term bonds, notes, and IOUs from high-quality issuers are used interchangeably with cash. And it's been this way for at least 150 years. Once the money market stops functioning economic activity grinds to a halt.
At least in 2008, there was maybe some moral hazard argument against the Fed intervening. From 2001-2007 banks and other financial institutions were playing fast and loose with their risk. Maybe in 2008 it might have made sense to let banks stew in the financial crisis they created to teach them a lesson.
But in this crisis what would be the point? This is a pandemic that came out of nowhere, that nobody could have possibly been prepared for. "You guys should have really had a contingency plan for global quarantine" doesn't make sense. I'm not even that big a fan of the Fed, but if there's any time ever to print money to prop up the economy, it's in the middle of a literal global pandemic when the government can already borrow money at zero percent interest.