For starters the 300,000+ people employed by those two companies (Chevy is GM). Perhaps you meant to include Stellantis (Chrysler) which would make that number closer to 600,000 people. The auto industry was a big driver of the 2008 crash.
That’s before we even start to get into the issues stemming from a Chinese monopoly on the auto industry. What happens if American, Japanese, and European auto makers go out of business and then China stops the subsidies? We will literally be in the same situation we are now but with money going to China instead of paying domestic workers.