We train people in their technical role, but we (generally) don't train people to manage -- and years of poor experience don't count.

I'm not a manager, and I don't want to be. But I'm quite happy with the manager training that my employer puts people through before giving them direct reports.

One should always be negotiating expectations, though, even when one considers management to have our best interests in mind. And also remember that your manager is learning how to manage from you. You get to shape their experience of being a manager, and you get (to an extent) to guide them in how they grow as a manager.