So what is it specifically that makes perl suitable/better for these applications?
Libraries. Modules. CPAN. I'm not going to say that Perl is better than any other niche language in science. But I am willing to argue that it is no worse than python/java/ruby/whatnot for general-purpose scientific computing.
The proof for this is my personal experience. I am not married to Perl in any way. My data is more important than my favorite language. So I said to myself; the day that I felt held back by Perl, I'd leave it (albeit temporarily) for the next better tool. And even though I've been only coding for a couple of years, that day has yet to come, and I've used a wide variety of data-crunching modules.