> It took a very long time but finally it was decided that Perl 6 wasn't really Perl 6, but some other, Perl-like language, and renamed to "Raku" to signal this. But by then it was already too late, most everyone had already moved on, and by the time when Perl 6 was finally released it was an extremely niche thing very few people had any interest in.

I agree with the rest of your comment, but I would like to emphasize the ordering of these events: first "Perl 6 was finally released", and only later was it "decided that Perl 6 wasn't really Perl 6 [...] and renamed to Raku to signal this". It was too late not only because most everyone had already moved on (by the reasons you mentioned: why would anyone invest in Perl 5, when the migration to Perl 6 would throw away all that investment?), but also because Perl 6 had already been released under the "Perl 6" name.