You're either misunderstanding Python 3 or misunderstanding Perl 6.

Python 3 was a few breaking changes made to Python 2.

Perl 6 was a completely new language, designed from scratch, with little in common with Perl 5 aside from bits of syntax. It still doesn't have a "complete" release, in 14 years. In half that time, we've had a Python 3.0 and four more point releases.