Who cares if your clock slows down say 20% by 50? Think how easy it is to optimize any program by 20%. It's irrelevant. Much more important is what software you're running. Like other posters here, I struggled with things in my 'prime' that I now find much easier. That phenomenon doesn't seem to get talked about much. There seems to be this truism that intellectually challenging work peaks before 30. How many great novels or plays were written by anyone in their 20's? Yet important math and music is often done young. Go figure.
I dunno about novels or plays, but Orson Welles was 25 when he made Citizen Kane.
I think it all matters on how accessible the medium is to young people. Modern music is VERY accessible, because there are so few limitations that you can really do whatever you want and while it may not be good, you've got a better chance of its being so since the concepts behind music are comparatively simple.
If we were talking about the world of composition, on the other hand, things would be much different. I doubt that we'd see many young brilliant composers, unless they were Mozarts (i.e. helped along heavily by parents).
