Perl 6 has recently changed its name to Raku. This means that virtual/perl6 should be renamed to virtual/raku. Reproducible: Always
I guess that's mostly up to Patrick. I doubt anyone from @perl objects.
I'd propose to simply delete the virtual at this point. It might've made sense back when dev-lang/niecza was still in tree, but that was eons ago, and there's been zero progress on adding anything that'd $depend on the language anyway.