There are plenty of reasons not to publish on CPAN. Not everyone has time to "babysit" all the modules they write (and deal with people's complaints that they're misnamed, aren't complete enough, etc).
Also, lots of people who were once productive on CPAN years ago have "gone dark" in recent years. Generally has something to do with having a life (fulltime job, family, that sort of thing).
So all in all that's a pretty snarky question to ask. It's definitely a plus to show that you have the sense of civic engagement to go through the full-fledged publishing process on CPAN (including processing testing reports, RT issues, etc) but it should suffice to provide code samples with clean coding style and decent enough documentation (even if it's a well-written README).
Also, lots of people who were once productive on CPAN years ago have "gone dark" in recent years. Generally has something to do with having a life (fulltime job, family, that sort of thing).
So all in all that's a pretty snarky question to ask. It's definitely a plus to show that you have the sense of civic engagement to go through the full-fledged publishing process on CPAN (including processing testing reports, RT issues, etc) but it should suffice to provide code samples with clean coding style and decent enough documentation (even if it's a well-written README).