I use Perl in my day job and enjoy it a lot, but the biggest showstopper for me is that its greatest strength is its greatest weakness. "There's more than one way to do it", it's amazing at getting things working, it excels at writing "glue" programs to shim between bigger and slower moving parts, especially if they're throwaway hacks.

However all that flexibility means that it's not possible to run static analysis with full confidence. Yes, tools exist - but it's been proven impossible for them to catch all cases, and this uncertainty carries real risks for critical business processes.

When you have a code base encompassing a set of core modules, with hundreds of auxiliary programs using them across the business, then any attempt to update perl or its modules grinds to a halt. It's impossible to even enumerate which programs will be impacted by the change with confidence, let alone the effects of such a change.

For details see "Perl Cannot Be Parsed: A Formal Proof" (https://www.perlmonks.org/?node_id=663393). You can mitigate the impact with coding style guides and code reviews but once the damage is done it's very difficult to untangle an existing code base that loads modules at run-time and makes full use of Perl's flexible nature in other ways.