"Having two programming languages that are sufficiently different to not be source compatible, but only differ in what many perceive to be a version number, is hurting the image of both Perl 5 and Perl 6 in the world," she wrote. "Since the word 'Perl' is still perceived as 'Perl 5' in the world, it only seems fair that 'Perl 6' changes its name."
2) The EXACT same thing could have been said about the Perl 4 -> Perl 5 transition, which, incidentally, was before semver was something that had to be explained.
3) People saw the periodic table of operators about fifteen years ago, and said, "Nope. Nope. Nope." No one ever expected Perl 6 to run Perl 5 code. There was some initial hope for sanity, but nope, nope nope.