tl;dr: When someone transitions to be a manager, they choose a new path in their profession. Going from a non-manager employee to a manager is not a promotion.
Opinion: Promotion implies that you have advanced in your career. Management is generally attained when you advance in life. Life does not necessarily equate career, or vice versa.
Fact: People are the center of a manager’s responsibility. Technology or the core of the business is the center of a non-management responsibility.