You could be 60 years old and have just started learning software development last year. The funny part? That still doesn't necessarily tell you much about the ability level. A year of development experience does tend to put an upper limit on how experienced you would say this hypothetical 60 year old newbie is, but it does definitely depend on his/her existing skills and education.
Or you could be Don Knuth, he's 71 right now.
Or, you could be a 60 year old who never got a good education and doesn't care to.
Knowing someone's age tells you how long it's been since they popped out of their mom. That's it.
[1]: Obviously there are people who judge based on age, regardless of legal, moral, or practical reasons not to. What I mean is that age, on its own, doesn't mean much.