I have the same experience. Multiple companies with a crazy manager that bullied and insulted employees. The bosses never do anything because the manager is always right.

At my last job I was the only developer who knew bash and Linux. I handled everything until a new CTO came and destroyed the servers with his lack of technical knowledge.

I was critically useful to the company until I broke down due to the daily harassment. I became valued the instant I gave my two weeks notice, but I still told them to go to hell.