This is a deep and interesting question, Mutable.
As the moon is the closest astrological "inner" planet to earth, and symbolises our "animal instincts" - perhaps the answer revolves around humankind's evolutionary development, symbolised by the recently discovered "outer" planets.
If we accept that Uranus, Neptune and Pluto were each discovered only when the consciousness of a "required number" of people had evolved sufficiently to become aware of them - and that the numbers of these "consciously aware" individuals will constantly increase, until the evolutionary characteristics of these planets become commonplace qualities in the individuals and societies on Earth - then, at that point, we will have evolved sufficiently to be in complete control of our instinctive behaviour - (like the Vulcan's in Startrek) - and there will no longer be a need for a moon "above" (in the heavenly zodiac), because it will no longer symbolise what is "below" (in the individuals on Earth).
So, if the moon was destroyed, the rate at which humankind evolves into it's higher octave of consciousness (symbolised by Neptune) would
neccessarily be accelerated - and (given our current levels of evolutionary consciousness) it's likey that the majority of us would be unable to cope with that - and might even be driven insane by the inevitably intense Neptune testing that would ensue.
[Let's hope it doesn't happen in our lifetimes, Mutable
]
Ben