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.
Scenario: A hard hitting priority has come up. The team handling this has other priorities and cannot take it on without burning themselves out.
Manager’s Role: Managers ensure that a priority is well understood from a macro perspective by the people on their team. They help to increase productivity by removing road blocks, increasing understanding and balancing the business’ point of view of the team with empathy. This requires negotiating other priorities, hiring or transitioning people and leveraging help from peer teams or lateral technologies.
Non-manager’s Role: Senior engineers focus on helping craft and execute solutions best suited for the scenario. They explore alternatives, influence people and inspire thinking out of the box. They execute with consistency and ensure repeatability.
This is of course not the only way to bifurcate responsibilities, but is a view into how management and individual contribution (aka, non-management) can differ. While one focuses on people and business, the other helps execute on technology and integration.
Conclusion: Management leap is thus not a progression of one’s career, it is a transition to a different focus area. It is not for everyone, and certainly not superior to other roles.