$ which perl
/usr/local/bin/perl
[download]

That's probably very relevant. It looks like the system Perl.

No, it doesn't. System perl is usually in /usr/bin, /usr/local/bin is reserved for locally administrated stuff outside the distribution. See also https://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard.

But then again, as several scripts start with #!/usr/local/bin/perl, it is quite common to have a symlink /usr/local/bin/perl pointing to some perl, e.g. /usr/bin/perl.

Alexander