That's a good question I've been pondering for a while and still don't have a great answer for.
I think some of it is that one degenerate form of leadership is to conflate it with authority, and a lot of people's experience with "leadership" is simply to receive orders.
I actually would call what you describe as the ideal form of management, which is not leadership either. An ideal manager is not simply an authority user/abuser, but someone who clears obstacles out of the way and works to enhance the ones they are managing's skills, but ideally, only a bit of authority is deployed, and a manager may in fact exhibit no leadership at all. (For instance, corporate goals may simply come from higher up, or market pressures, or things other than "leadership" per se.)
(There are also degenerate cases where raw, naked authority is in fact necessary and extensively used; I'm sure a lot of us worked a job at McDonalds or some rough equivalent and have memories of how much it was based on authority... fewer of us have experiences of managing in that environment and being directly exposed to the fact that it is just the only way to make it work, however distasteful you may find that fact.)
For me, leadership should be reserved for the cases in which one is visibly leading, e.g., you start a new initiative somewhere, gather up people to voluntarily follow you by a variety of non-coercive means, and then hold the group together in a variety of very context-sensitive means.
True leadership is rare. Authority is inescapable, good management is a gem to be treasured but still not that rare, but leadership is a rare thing. Most groups are held together by other bonds.