That's not going to happen. The German industry itself doesn't support protectionism because virtually all carmakers are heavily invested in the Chinese market both for its consumers and for manufacturing.
Audi last year alone invested 3 billion in a new factory in Changchun[1] together with FAW. Anti-subsidy investigations from the EU are not going to result in any major trade issues.
[1]https://www.audi-mediacenter.com/en/press-releases/cornersto...
Ironically, China has been one of the primary economic beneficiaries of the postwar Pax Americana. Their merchant ships have been able to travel freely throughout the world without incurring the expense of building a true blue-water navy to protect them. This situation will gradually fall apart over the next few decades.
No one is seriously claiming that global trade will disappear. But from a historical perspective the current frictionless system that most people take for granted is an aberration and we should expect some reversion towards the mean. Whether that's a good thing or not is a matter of perspective.