The problem is that right now the choice is between:

1. A good programming language (p5) plus all of CPAN; or
2. An awesome programming language (p6).

In almost all cases CPAN wins that fight.

An interpreter for Perl 5.x code (even if it only works on a very large subset of CPAN), that runs in Parrot, and allows Perl 6 code to call Perl 5 libraries, instantiate objects defined in Perl 5 classes, etc, could massively swing those scales, but right now that doesn't exist.