Seniority was airline managements best invention. It contained movement of an expensive resource allowing to lower pay over time as they needed to worry less about loosing experience.
We're our own worst enemies.
As for the guy at the top not leaving. I can't understand why they should. The problem isn't the guy, it's a system most fall into, and by the time you'd fight away with it you'd be at the top loosing out on the perks.... until