Perl is not that good a language though for practical purposes. The same way, a breadboard contraption is not what you want to ship as your hardware product, but without it, and the mistakes made and addressed while tinkering with it, the sleek consumer-grade PCB won't be possible to design.
With a team where everybody wrote it in a similar style, Perl did perfectly well. Mod_perl was fast. I liked Perl.
Then Django came out, and then Numpy, and Perl lost. But Python is still so incredibly slow....
It has so many great pieces of advice that apply to any programming task, everything from naming variables, to testing, error handling, code organization, documentation, etc, etc. Ultimately, for timeless advice on programming as a profession the language is immaterial.