Unbelievable... Reading some of these replies makes me ashamed of having such colleagues.
I've flown with "old farts" who were great Captains and leaders, who had good people skills and were very nice to fly with. I've also flown with "old farts" who were exactly what a Captain shouldn't be and they were a good example of what sort of Captain I don't want to be. (I think some of them are active on PPRuNe.)
I've flown with FOs in their 20s who were hard working, humble, eager to learn and motivated for the job they did. I have also flown with FOs who were the opposite.
So please stop the generalisation of age groups.
Some people forget that they once were young and inexperienced themselves and that they probably had to put up with older Captains who didn't think too much of them either. No matter how good their intentions were.
Do you expect someone who only had experience flying short haul, to know everything there is to know about flying long haul all over the world? Everyone keeps learning, even the "old farts", but not everyone will admit it.
I like learning from experienced captains (the good type of Captains), just like I enjoy passing on some of my experience to other FOs (the good type of FOs). Isn't that what colleagues should do, instead of arguing on an anonymous forum?