It's also interesting to note that the 773, I believe I read elsewhere, actually has a longer wheelbase (if that's the technical term) and turning circle than the 380, so in theory it may be easier to manoeuver than the aforementioned 773.
I recall, many years ago seeing a British Midland F27 skillfully (??) taxied on to the grass opposite the old terminal - when it was still the only terminal. That didn't make BHX incapable of handling the F27, but it did make the driver look a bit of a pratt!! (No suggesting for a moment that the same could be said of the captain of the Emirates 773).
Whatever the rights and wrongs, a bit extra concrete on both taxiways and runway would never be unwelcome.