I'm not ready to write off GM (or other US car companies) forever. I'd put them into my decision matrix if their current models were giving 200K miles/10 years of trouble-free service, comparable to Toyota and Honda. But it takes 10+ years to get a reputation like that, and they've made promises over many years that "we've learned and now we are doing things really well" and it often hasn't turned out that way. So, I will remain very [-]suspicious[/-] skeptical.
I recently had a 2017 Chevy Cruze as a rental car, and drove it 1200 miles in two weeks. I was surprised--it was a nice little car. The fit and finish were good, it got 44 honest MPG on the highway (at 65-70 MPH, and no particular effort on my part to economize), the ride was quiet and smooth (for a small car). It had a small 4 cylinder turbo engine that produced good acceleration and was smooth. If they'd been making them (or similar models) for a decade and they had proven to have Civic/Corolla reliability, I'd consider a Cruze. But, for now, the Chevy reputation (including the previous Cruze years/body styles), the start-stop engine control (getting more common--maybe it will prove to be okay but it is an irritant in my opinion), and the inclusion of the small turbo on the small engine (another thing to go wrong--and marrying the turbo to the start-stop engine feature seems to be inviting eventual problems with turbo bearing coking) would all give me pause.
It takes a long time to really turn the corner and build a quality car. It's not just a design issue or making sure the cars are assembled right in the GM factories. It also requires the establishment of good relationships with suppliers of everything that GM doesn't make--pumps, switches, gaskets, bearings, electric motors, brackets, sensors, etc, etc. These suppliers need to know that GM will track the reliability of these parts over 10-15 years and reward or punish them accordingly in their future dealings. That's what it takes. So, it might require a couple of decades to weed out crummy parts and establish a sterling reputation for GM products. So far, GM isn't there.