Why do you keep saying Perl 5 is not doing well?

Where did I say that? I think you're reading a lot into specific technical criticisms of Perl 5.

Worse case, all those learnings can be pulled back in to Perl 5.

In 20 years of gradual evolution perhaps. You have to change many, many things, including the basic container/value model and the Perl 5 notion of type morphing, to make a lot of Perl 6 features possible.