GM was bankrupt because of their union pension plans, full stop. The pension plans cost more than all the active union workers. Blame anyone you want to for that, the future of manufacturing is all robots anyhow.
Not true. They went bankrupt because they sold crappy cars which cost them a fortune in warranty repairs.
I purchased a GM car in 2005. By the time we got rid of it in 2009, it had received the following repair warranties:
2 wheel bearings, 3 steering columns, 2 ECUs, 5 replacement door hinges, 2 brake discs, 2 auto transmissions and 1 door window motor.
In compensation, we were promised a $400 check but we never did receive it and to be honest, I don't care. We don't have the deathtrap anymore.
With all the billable hours that the vehicle spent in the shop, the vehicle must have been a big fat loss. Given how busy they were fixing up other vehicles, ours wasn't a unique case. This is what made GM go bankrupt.
I have never had a vehicle which was so unreliable before or since. As a consequence, I shall never buy another GM vehicle.