GM actually had it figured out, and then the Democrats screwed it all up. They built and sold cars for different aged people. Young people wanted small, fast sporty cars. Middle Age wanted bigger cars to haul kids and go on vacations. Retirees wanted big luxury cars. The mileage standards required by the government has really reduced the big luxury cars. So, GM tried to switch from large luxury cars to smaller sports sedans that were “like BMWs”. BMW owns that market. Let GM make big luxury cars again, without the UAW, and they’ll do fine.
Therein lies the hang-up, the UAW owns a sizable chunk of GM stock and doubtful they'll be ousted.