Robots already build cars, and supply of new cars is often out-stripped by demand. It's not really new ground.
The limitations in car production are always the component supply chain, not the actual manufacture.
The limitations in car production are always the component supply chain, not the actual manufacture.
But to see how much robots actually do nowadays, compare that to auto assembly from decades ago when robots were new, or further back when they did not exist
GM is of course tied in with the UAW, so they're going to be as favorable to labor as possible in their promo videos, but take a look at this video of one of their production facilities, this is reflective of the amount of manual input into modern automotive production:
Especially customisation and snapping delicate plastic trim pieces in place is still done by hand.
My rule of thumb is that there is about 10% of manufacture cost that are direct or indirect cost connected to payroll.
If I may add another axis of reflexion that I consider fundamental for modern engineers to consider, food for machines for producing a car (44% natural gas when smithing things) is about 15 to 25% of the energy cost to use the car in its lifetime, according to the EU. Or about 2,400 euro of a 8L/100km car.
So in a world where energy gets more expensive, automation needs to definitely evolve, but not solely to be faster or replace more humans.