We need to phase out cars. There is no solution in sight to make driving around >1000kg for an hour a day sustainable for everybody. At least 9/10 cars need to go. That still leaves plenty to serve special needs.
Germany is often cited as the most heavily automotive leaning economy. WP says the industry employs around 800k people. Germany's total workforce is cited at 44 million.
Some of that workforce would be categorized as being in the industries of manufacturing, engineering services, chemical products, electronics, etc.
In Michigan, for example, there are many hundreds of non-automotive companies who rely on nearby automakers for virtually 100% of their contracts.