The parent was making reference to the common notion that using outlier languages provides access to high quality talent. In certain cases this holds true, in others not. You will attract, on average, higher quality talent by using Clojure rather than Cobol.
EDIT (response to parent edit) : well, no. I never said there are "no good Perl jobs", just that Perl is not in and of itself a draw in the way that Scala / Clojure / Haskell might be. You could probably convince someone that there are cool opportunities in Fortran development, but very few are actively seeking them out.