Banning German cars just for being German would be stupid and repeating the mistakes the Soviet Union made. If someone wants a foreign made car, then you are reducing their quality of life. It may not be a big deal if it was just limited to cars, but the effect would be exacerbated if extended to other consumer products. Besides, there's also no need to. The trend looks like Chinese quality will meet and exceed western quality. If anything it'll be the west banning Chinese cars.
Why would buying South Korean or Japanese cars be any better than German ones? If you're attached to the American imperialist teat, you're just as bad as them. From the Chinese perspective, the Japanese are much worse than the Americans.
Discretionary spending for who? Maybe for you, but I need a car to work, transport my family, etc.
LOL. European cars would have no chance against Japanese ones. Look at any market where both are allowed to compete equally. That's why the Europeans tariff Japanese cars to give their domestic manufacturers an advantage. Even still, Japanese cars are quite popular in Europe.