Despite being a pythonista at heart and a rubyist at work, Perl is still my go-to language for when I notice bash scripts getting messy and growing out of scope and destined to enrich my personal long-term unix toolset.
Yes, Perl is still very relevant today, for me and for countless others[0]
1. It's everywhere. By that I mean my code will work everywhere, without much thinking about it being installed, versions, or packages, or whatnot.
2. Ruby is too 'core' and needs too much additionals gizmos to be efficient
3. Ruby is concise and conventional, while implicitness and terseness are idiomatic of Perl
4. I'm no Perl monk but things in my head translate to code structure more easily in Perl for this use case (unix tools, text/binary/file content stream manipulation)
5. Perl strict mode
6. Occasionally, Perl suid support
7. Bonus: performance under Windows, or rather lack thereof for Ruby
Mind you, Ruby is extremely apt and I enjoy working with it (especially - but not only - with Rails), but this is more a matter of using the right tool for each problem.
Yes, Perl is still very relevant today, for me and for countless others[0]
[0]: https://github.com/languages