|Think about Loose Coupling|
In short, Perl 6 might have been basically a re-iteration of Perl 5 in the same way that Perl 5 was for Perl 4. Only this time we could break backwards compatibility to fix some of the hairier bits.
The problem is that--with that process--it still takes eight years to build Python 3, and then you don't get an object system like Moose, you probably don't get pervasive laziness, you don't get pervasive closures, you might get hypotheticals, you don't get grammars, you might get continuations, you probably don't get custom operators, you might get multi dispatch, and you probably don't get a rethinking of context and the type system.
You might get multiple implementations cooperating around a canonical specification. You almost definitely don't get a self-hosted grammar as part of that specification.
You don't get roles.
You get Perl 5 with some of the worst bits of Perl 1 - 4 removed. Yippee.
Also you're very, very wrong about the JVM. Invokedynamic is only the start, unless you want to throw away partial binding, multiple dispatch, continuations, coroutines, lightweight concurrency... or spend the rest of your life writing trampolines.
In reply to Re^3: A wholly inadequate reply to an Anonymous Monk