No, teach them better. Management is still needed. A manager should be able to increase revenue, or at least productivity. If all they can do is reduce wages, that's a pretty low bar. Any asshole could do that.
Separate the functions out explicitly, as needed.
Often they're just corporate prison guards in organizations with bloated structures and antagonistic views of staff from an executive perspective.
Flatten your structures so the highest-level strategy is connected to your lowest paid staff. If you can't do this, then you have a toxic company that resembles prison labor and the whole thing deserves to fail.
Oh, you forgot Politician.