That is probably true with regard to its adoption, but, as a Perl fan and user, I have to say that in addition, the limitations of Perl 5's syntax begin to show once you get in to collections of collections, and passing them to functions. If you are doing this sort of thing every day, it becomes second nature, but as a casual, ad-hoc user, it is no longer in my working memory.

Maybe Perl 6 fixes these things, but learning it is too far down on my to-do list, where it sits just below Ruby.

If I have a problem that can be solved by looping through the lines of a text file and applying some combination of regular expression matching and substitution, the split and join functions, simple arrays and hash tables, I reach for Perl 5.