For many people, men in particular, their work is their life. For some, time away from family makes the time with family that much better, for others, they just need to be away. At work, they have a captive audience and are surrounded by people who share their interests and understand their lives. This applies to all industries, not just pilots. As women become more career oriented due either to desire or opportunity, they, too, will fall into the category of those afraid or unwilling to let go.
People used to retire at 65 and be dead at 66. If you made it to 70 you were doing well; to make it to 80 was extraordinary. With the current epidemic targeting the elderly, this will again become the norm.
If you want someone to step down so that you get the chance to step up then deriding them is the wrong way to go about it. When you ride with an old timer, tell him stories of what you will do when you retire, how you will travel the world at your own leisure, sleeping at night and not chasing sleep all day. Put dreams in his head about sailing adventures and Tiger Moths but don't suggest cruising. Paint the picture for them if they cannot see past a life of work for themselves. Be subtle, not aggressive, friendly, not nasty, mature, not a 2 year old.
Of cause, you probably aren't riding with anyone at the moment and can't even put dreams about at the pub but when you go back to work in whatever capacity, be smart about upsetting the people on top of the pile or they may just stay there a little longer just to keep you in your place. Who could blame them.