We've established that, and I'm happy to agree that you're wrong, and you're happy to agree that I am.See, this is where we agree. Unfortunately, there's not much more we can say, though, because my opinion doesn't match yours after that.
Anyway, back to the real issue at hand:
Crabmen = new hotness
Dragonborn = old and busted
Clearly, crabmen in the core serves the most people. It's subjective, but just as appropriate as dragonborn in the core, because they both belong in every D&D campaign and world equally as much.