Investors can “happily pick up the pieces” all they want, but actually doing something with those pieces is another matter entirely.
The first thing that’s going to happen is that folks are going to stop buying the cars. (According to one survey I heard, a majority of people have said that they won’t buy a car from a car company that files for chapter 11, so forget about people wanting a car from a company that most assuredly won’t be there.) While investors might be willing to buy up the assets of GM or Chrysler, how many banks do you think are going to be willing to underwrite a loan so someone can buy one of the cars?
People who already own a GM, Ford, or Chrysler vehicle are going to be very eager to dump theirs, since they’re going to be worried about finding parts. (Yes, yes, I know, I know, there will be people who’ll continue to stock and make the parts after the company goes under, but that’s not really going to sink in with most of the general public.) Not to mention, unless the government steps in, people who have a relatively new car are going to have to pay for any repairs, since there’s no one left to honor the warranty. So there’ll be a glut of used cars on the market, which will drive down the value of those, unless they happen to be made by a foreign company.
There will also be job losses, lots of them. With no new models rolling off the assembly lines, and a relatively low demand for spare parts, you won’t need to keep as many people employed. Starting a new company out of the ashes of an old one, isn’t necessarily going to change this, either. You trot out an '09 Chevy with a new nameplate on it, and people are going to look at it with a rather jaundiced eye. To entice people to buy the cars, you’re going to have to sell them very cheap (which will paradoxically disincline folks to want them, since they’ll figure the quality of the car must be even worse than what it was before).
Any new business that tries to make a go of things is also going to have all kinds of supply chain disruptions to deal with (critical people will leave, businesses will go bankrupt, etc.), which will further hinder efforts at gaining traction in the market place. It will take a long time to sort out the mess, and it will make it that much harder for the economy as a whole to rebound.