Thanks for your point, Raymond (and have definitely heard good things about Leadership BS). I agree that separating leadership and management to some degree is harmful. Good leaders are usually good managers.
While it’s important to be aware of the consequences of the distinction (as put by Bob’s points in your post), the two deserve to be separate concepts. I don’t think they’re “essentially” the same thing. How else can leaders learn to develop the skills to take on the “hard work of learning about the people they lead”? Is this not a problem of managers who lack true leadership skills?