Before Perl, there was no scripting language that could do systems tasks except maybe shell and tcl, but that's shell is an extremely unpleasant programming experience and the performance is horrid, and tcl's string-based nature is just too weird.
Perl gives you something more like a real programming language and can do shell-like tasks and systems tasks very nicely. Compared to what came before, it is amazing.
But then Ruby and Python came along and checked the "real programming language" box even more firmly than Perl while retaining the shell/systems angle. Ruby and Python were better than Perl along exactly the same axis as the one on which Perl was better than Tcl and shell.
It is a real general-purpose programming language, not a "scripting" language. Did you ever have a look at it?
I wonder if there was an earlier point of Perl's demise. Perl 5 came out with flexible object-oriented features, but it took years for packages like Moose to come out and make it nice and usable.
But the bad side was that by the time someone was clever enough to invent Moose, all sorts of other bespoke object systems had been invented and used in the meantime, and your CPAN dependencies used every single one of them.