Well there is a theory, in reality, of Mutiple Histories. Basically every possible outcome of an event happens, and the result, mutiple histories occur simultaneously. It'd be a headache to apply to the Zelda Timeline though.
The very fact that events within the 72 hour timeframe would automatically reset, regardless of Link playing the Song of Time or not, suggests that Termina's destruction by the moon was not the predestined outcome. Inevitably Link had to stop the collision of the planet and moon, and that was...