I'm starting to believe that Sanji is the current JoyBoy. Back then at Fishman Island,Sanji said he fulfilled his dream (jokingly) by finding a place full of beautiful mermaids,and that was his "All Blue". When you put this together with the destruction of the Red Line theory, everything makes sense.
FI is directly below Mary Geoise,and in order to make the "All Blue" one would have to break the boundary between the seas,therefore destroying part of the continent. Most versions of the theory talk about destroying the Reverse mountain,but I think destroying the capital city of the WG makes more sense in a symbolic way.We already know about Noah and the future of FI,but what if Sanji is the one to fulfill the promise to move the Noah and destroy the island,and not Luffy? I've been thinking about that,Luffy never wanted to be "the chosen one",he wants to be free,but Sanji's dream is directly related to this whole thing. If Sanji is truly the new Joyboy,then this one panel makes sense. He would be the most wanted man ever.
Maybe I am brainstorming a bit but someday maybe I will write down everything in order make things more fleshed out.