I predominantly work in Perl 5, which probably isn't quite to the point of being something one can write off completely as out of the spotlight. And, I'm launching a new thing soon which, despite having looked at a number of alternatives, will likely also be in Perl. Familiarity and a big ecosystem that I'm already familiar with is a pretty big win.

I happen to work in the systems management space, which was long dominated by Perl (Python ate into that space starting a decade or so ago, and Go is now making significant inroads, but Perl is still pretty common), so the libraries are very strong. I may end up writing the prototype in Perl just to get it launched, and then rewrite the parallel parts in Go. It is an embarrassingly parallelizable problem, so Go or another language very good at concurrency would be reasonable. But, I find that learning a new language and tackling a new problem space at the same time is challenging. The front end will always be JavaScript, though. Probably with React.

And, I've been working in PHP a bunch lately, because our website runs on Drupal. I would never use PHP except to get access to the massive piles of existing functionality out there already in PHP. But, nonetheless that makes a pretty compelling case for using PHP. And, maybe PHP is still popular enough to not fall into this category. Heck it may even be growing, given the popularity of WordPress, I dunno.