Old people, in general, don't have literary careers ... most writers begin to attract attention - as new young voices with something original to say.Robert McCrum in The Observer today has some sobering things to say about authors and age, backed up with plenty of interesting examples.
Apparently, authors are most likely to produce great works in their 30's and most literary careers last no longer than ten years.
He reminds us that :
As a writer, you are always starting out afresh. Age and experience may teach you some tricks, but it will not touch your work with magic.(Pic is of one of the exceptions to all this - 91 year-old memoirist Diana Athill, one of the finalists in the Costa Book Awards.)