By the time Perl 6 was around, Perl's lunch was already eaten by Python. Only a few table scraps left. Perl 6 would have had to be a better Perl 5 and a better Python 2 to win.
Python came with better batteries and better syntax. It allowed producing code you could read and understand a week later. Perl I found was a write-only language for me. I went back looking at my old Perl code and I couldn't decipher it without some effort.
And Python became popular not just because it was a better Perl, but it attracted folks who used Java and C++. CPU speeds were getting fast enough that you could actually do file and network IO at acceptable speeds without all the `public static void main(String[] args)` and `System.out.println(...)` boilerplate, but still had all the object oriented bits like inheritance and composition with which you could go crazy with if you wanted.
Don't sell perl 6 short. I am using perl 6 for significant projects now (after a career of perl 5) - and it's fundamentally different. I describe it as perl to the power of perl.
For me, expressiveness is fundamental. And perl 6 gives me that.
Perl 6 is simply suffering from python being everywhere. And perl 5 was always easy to lampoon as "line noise". It's a stupid quip, but it leaves a mark on new programmers. You don't even need to read the course and you can already have an opinion. Stupid kills? And then perl 6 doubled down on that anyway. Then I doubled down on that ALSO and I get to use (carefully chosen) unicode symbols in my line noise :-) So there.
I saw Larry Wall at one of the conferences. He talked a about Perl 6 how it was progressing and such (it was before it was renamed) and year, expressiveness what stuck out. It certainly has lots of nice features, too. But at least for me, I realized with Perl 5 I wasn't smart enough for it. I would be lured by the clever short expressions and then sometimes later look back and had no idea what I wrote.
Larry is a great person, btw. During lunch at the conference sat at his table and he was very approachable and warm. I don't remember what we talked about exactly just that it I liked how down to earth and nice he was.