I read that as: it gives the impression it's been here forever, it's still being actively maintained, and will be for the foreseeable future. Benefiting from the “future” (sqlite4/perl6) at a slow but steady peace. So, really like Perl 5.

perl5 has been stealing a bunch of stuff from perl6 and is still actively maintained and doing a major release with new features annually - also continues to Just Work with an extreme commitment to backcompat.

So I'm pretty sure he did mean perl5, and as a happy user of both perl5 and sqlite the comparison seems apt.