you are missing the point, once AI companies goes down it will take down the sp500 too. so their retirement accounts will be affected.

I think there's a bit of a difference between preventing a run on the banks and propping up the entire stock market for the sake of just a handful of companies that all have big enough pockets to fail.

covid crash and what they did in respond to market crash disagrees.

what are you referencing in particular?

sorry, wasn't that in response to a natural disaster? I don't see how we so easily sweep that into the same idea as "bail out".