Arch Linux drops Python 2

Given that Perl 5.26 dropped support for ISO 8859-x source code, it's not universal. Given that Perl 5.6 (2000) added (experimental) Unicode support, it's likely your code has problems handling certain text; since that version also added 64-bit support and support for >2GB files, those could also be problematic points. The world is a pretty different place; merely running doesn't mean they usefully work.