Is anything after Perl 5 relevant? Perl <= 5 is the duct tape hold many corners of the Internet together. I don't know anything significant after v 5.

The current version of perl is 5.36 (it's a really good perl). The language formerly known as Perl 6 is now called Raku. The "Perl 7 initiative" referred to in the grandparent is the idea that at some point, the 5.x series (i.e., the language you know as Perl) will accrue enough features and deprecate enough very old behavior that it'll get rebadged as Perl 7.

There's not a timeline for that right now, nor clear consensus on what exactly will be worth a version bump or how much backcompat between 5.x and 7.x there will be going forward. It's being actively discussed, though; the Perl Steering Committee (formed a couple of years ago) meets weekly, and discussion on p5p (the language development mailing list) is still fairly active, though admittedly much less so than in years gone by.

I believe Perl is integral to the OpenBSD package system.