Perl's just another language I've known. Maintaining a 20yo codebase in a language that people find distasteful sounds like comfortable job security, to me.
Most programmers want to build new things, not work on maintenance projects, regardless of tech stack.
That said, many people do enjoy that sort of work and finding them is not unusually difficult unless the project is so big that you need dozens of bodies.
Sure, but there aren't many programmers who would want to maintain such a system.