The minimum age of 24 makes some sense. This will reduce the number of resumes from low timers who would not be able to handle the conditions. Anyway, no sensible non-airline operator wants to hire a 250 hour pimple-faced CPL Top Gun wannabee who beats up every airfield on arrival, drives maintenance costs through the roof, cheeks the pax, smashes the freight, and turns up to work as and when it fits in with his party schedule and hangover recovery ability.
When I posted above I was thinking more of the upper age limit. Apart from human rights issues, the maximum age of 40 is self defeating. Pax like to see some grey hair and well worn stripes. It gives them confidence. The age 40 limit excludes a surprisingly large pool of pilots who have retired from the airlines and want to continue flying, have always stayed in non-airline pilot jobs or who have made a career change. Older pilots offer the maturity, wisdom, experience, work ethic and judgment that might not be available from a younger pilot. It's dumb to exclude such experienced pilots!