Listen to what a dinosaur has to say
I have recently returned to flying after a break of forty years. (Yes, it does get into the blood: the break in my flying career has been longer than most people's flying careers, yet here I am back again)!
Thus, I am in prime position to compare the flying skill of '20 year old me' directly with '60 odd year old me'.
In terms of actual skill in handling the aircraft, I definitely do not think I am quite as good a pilot as I used to be, although the decrement in performance is not great.
At the same time, I am much less vane about my own ability and I am very much more cautious and risk averse than I used to be. I try to be professional about my flying, even though I'm only a PPL.
So Paris Dakar is right. Yes, you do become much more risk averse with age because you are much more conscious than the young person about the physical, legal and financial consequences of accident, and you no longer consider yourself indestructible.
To reply (with great respect) to John Farley. I believe that finding you are not as sharp as you were is only a reason for giving up if the extent of the decrement in your performance is such that your judgement leads you to believe that you are no longer either competent or safe flying whatever aircraft it is you fly. If you really feel you are no longer up to flying your current type, (for example if you fly some kind of 'hot ship') you might be OK flying something slower. Short of that, I feel it is a reason to continue, if that is what you choose to do, but with an additional increment of caution.
To recall the old addage, 'the superior pilot flies in such a way thay there is a reduced possibility that he/she will have to demonstrate his/her superior flying skills'; a perfect description of the flying style of the older aviator.
Broomstick.