That's actually a great point. Perl has so many syntactic sugars that it is a poster child for too much variety in ways you can write things. Making it much harder to read someone else's code.
But you give up something to get benefits in those areas. Making use of the expressive power of something like Perl is a wonderful sensation. The barriers between thought and making it happen are lower, and so you can be remarkably productive. It is also just more fun, I find, which has subtle and under-valued long-term benefits.
But yeah, agreed that comprehending someone else's Perl-fueled vision quest can be ... rough (: