Do you mean to say that any mention of Perl 6 here is toxic?

Not at all. I mean that some discussion has turned toxic. I believe it would be unproductive to give specific examples, though.

Please keep in mind that 5 already copied 6 features, like Moose.

I think that's overstating things. (I contributed to the design and implementation of both.) P6 was an influence on parts of Moose, but Moose also influenced P6, especially to the degree that Moose influenced NQP and MoarVM—and Smalltalk, Common Lisp, and the Kiczales book preceded both.

... and that you used to be one of the main cheerleaders of this project.

I like to think I can learn from my mistakes.