It's not about their age. It's more about their bank account. When your rich your not near as hungry and just don't care as much any more.
Wither Jimmy Page?
In listening to the Old Zep classics I can't help but wonder why this guy's talent (which is immense) never accompanied him in his later years (look at Jeff Beck or Jorma Kaukonen for examples). Is it me or does it seem like he just dropped off a cliff? I know he's still making music but does any of his more recent stuff shine like his early stuff?