I thought the age thing was mostly to do with being able to get a job after mortgaging the children to pay for training. Sadly most airlines do not appear to share Genghis's enlightened point of view, and think that all over 30 are somehow a liability.
It is not stopping me however, I plod on regardless of my advancings years. Why? partly to see if I am good enough or not, but mostly because I want to and I can.