Originally Posted by 67Creek

Other than "that's how it used to be", what reasoning would lead to the conclusion that you are entitled to a higher seniority based not on merit or experience, but on being born on an earlier date?

Just about any potential factor I can think of (time spent committed to the company, part 121 experience, general flight experience, crew or military experience, additional ratings, past positions held, etc) would, to me, seem like more justifiable factors to sort seniority by. Years until mandatory retirement (the inverse of age) does seem pertinent, but I would think the airlines have a vested interested in keeping younger people happy, as they have more longevity--at least as far as regulations go.

This isn't a personal attack on your stance, I'm genuinely curious.