Being a leader and being a (people) manager are very, very different things. So, of course this isn't a guide on how to be a leader.

A good manager is absolutely a good leader, and v/v. In my experience, there is no role that, if done properly, isn't equal measure both. They are sub-set skills of any position to which people report. Be it middle manager (important to execute, important to give meaning and direction within that area) or C-level (CEO can't afford to be a non-manager).

I would disagree here. In my opinion, a good leader has to be a good people person (and ergo likely a good manager - not always though), by definition. A good manager, or people person does not always make a good leader though. In my limited experience, I would think that a leader would demonstrate an ability to expand boundaries more so. My use of good can be substituted with effective.

I see what you are saying - and maybe someone can get by in either job without being strong in both skills, but I guess the point I'm trying to make is that all people-management roles ideally have both things happening. So to actually be good/great at roles that people assume are exclusive either to leadership (e.g., CEO) or to management (e.g., good ol' middle manager), both skills are necessary. And the big difference between the above examples is scope/scale, not how much leadership vs management is necessary.

People management is very, very different than leadership.

Take Steve Jobs, for example. A complete asshole if not a full-blown sociopath, but an impressive leader capable of creating a cult-like following.

Leadership is about inspiring and driving people towards a goal. People management is about recognizing the strengths and shortcomings of individuals and helping each one of them to improve and achieve their best, as well as selecting and assembling the right team where members complement each other.

Often enough, the two roles are at odds with each other.