Apple don't keep their scripting languages updated. For example, macOS Mojave 10.14.6 ships with perl 5, version 18, subversion 4 (v5.18.4) in /usr/bin/perl; but my homebrew setup provides perl 5, version 30, subversion 0 (v5.30.0).
(And for those who don't know perl, it's been semi-permanently pinned at "perl 5" as a major version number for about 20 years due to the existence of perl 6, which is effectively a different language—as different as C++ is from C—so those minor version number differences are as significant as a major version number change in another language.)
Apple don't keep their scripting languages updated. For example, macOS Mojave 10.14.6 ships with perl 5, version 18, subversion 4 (v5.18.4) in /usr/bin/perl; but my homebrew setup provides perl 5, version 30, subversion 0 (v5.30.0).
(And for those who don't know perl, it's been semi-permanently pinned at "perl 5" as a major version number for about 20 years due to the existence of perl 6, which is effectively a different language—as different as C++ is from C—so those minor version number differences are as significant as a major version number change in another language.)