The factory equipment would've just been sold to foreign competitors in China and Mexico though.
Not necessarily; the goodwill & trademarks (such as it was) plus facilities could remain w/ US buyers.
Was it not? Grandstanding nonwithstanting, 15 years ago GM (and VW/Benz) were very active shifting assembly to Russia of all places.
You can argue that did actually happen. China invested in GM through their partnership during that crisis and in exchange got anything that was left worth having from GM. Now GM is an old husk lumbering along waiting to die.