It can definitely be worthwhile.

First, Perl takes some unique approaches to programming language design, and that will stretch your brain and make you a better programming. New concepts and ideas (to you), particularly ones with a long and proven record, are almost always worthwhile.

Secondly, Perl is incredibly useful. It's still my go-to choice for a most things that need more than can easily be done as a shell script, but don't have a specific reason why I should use a different language. I find that Perl is more fun to code, and it's incredibly efficient for getting things done. If you're doing anything that involves text processing, Perl is still king, IMO.

One note: Perl style shifted significantly about ~15 years ago with the "Modern Perl" movement. This was a good thing, and you should ensure that any books or articles that you work with take advantage of those modern approaches. This can largely resolve the "write-only" complaints that some people have about Perl. Which, to that point, I'll note that it is very easy to write very readable and easily maintainable Perl code. Use a recent version of Perl and make sure you always have strict and warnings enabled!

Also, if you're wanting to do OO, check out Moose, Moo, or Perl's newly released OO class system.