Firstly a link to The future of perl and to a recent video at fosdem: perl in 2025, just to have a real background for the discussion.

That said I'm not at all qualified to speak about perl evolution but in the years I noticed that p5p tend to keep perl core as tiny as possible because this helps a lot the maintenance. Being CPAN so important for perl and perl developpers the concept of upstream/downstream was introduced to spot with easy those perl modules critical for the user base: see river of cpan.

About human languages: there are loanwords and there are cognates. My mother tongue is nowadays full of loanwords and in my opinion they impoverish the language, overlapping or replacing words and expressions already present in the language. This is a matter of fashion and ignorance, mostly. I'm not a purist and I know my language absorbed a big lot of words from everywhere and in every epoch. I dont wont, as in French, a word in French for every damned part of a computer, ordinateur they say. This resistance make me smile. Something in between must exists. Anyway Latin has not died: it evolved into many Romanic Languages and influenced other langues too. What the carterpillar calls "end of the world", the rest of the world calls it "butterfly".

So a concept or a function cannot be cut and pasted into perl: they must be digested and incorporated smoothly. How long are we waiting for signatures? I suspect signatures pose serious implementation problems and cannot be just put as is in the core.

We had CGI for long time, and the web evolved under our feet. Other younger languages developped different approach to web serving. Ruby give birth to Sinatra: perl geeks looked at it they seen as a good thing, so they made Dancer and now we have PSGI and plack and Mojolicious and many better tools (ok: the order might be wrong but the concept is clear :).

So we cant make a Frankenstein language: we must assimilate concepts and implemnt them in a smooth way. At least this is my opnion.

You mentioned GUI and parallel programming. I do not concord on this and for sure is not the reason of fewer users. We have long standing tools like Tk and Tkx as GUI frameworks and they still serve very good. We also have a newer promising one Prima. About parallel programming we have MCE, a huge and succesfull effort by our brother marioroy to bring highest computational power to mere humans.

The strength of perl, imho, is in its stabilty, realibilty and portabilty and to be a multipurpose first class languange. Only with core mudules you can already do a lot of nice things, for the remaining there is CPAN.

L*

PS 2021 April 12th: today I was pointed to "saving" perl at p5p and in is an interesting reading.