You bring up an interesting cultural question. I didn't name PCRE, so I'm not sure I'm obligated to come up with a replacement.
But if we can manage to give away the engine this time so that people don't feel obligated to reinvent it compatibly, then we could just call it "Perl 6 Rules". Or
in Californian: "Perl 6 Roolz, dude!" And then PCRE could just become one of those rebranded acronyms that people forget the original meaning of, like PIN: "Please identify yourself by typing in your personal PIN number..."