Now that the issue of "discrimination" has reared its ugly head, no one can give a straight answer to your question. By that I mean that any explanation of why

Now that the issue of "discrimination" has reared its ugly head, no one can give a straight answer to your question. By that I mean that any explanation of why people over 30 really are worse programmers, will be interpreted as "discrimination" and therefore wrong. Any explanation of why people over 30 are better programmers, will be taken as evidence that there must be a lot of discrimination since the older programmers are not only not worse, but better.