Haruhi=God is merely an interpretation of Haruhi's power by a small faction of the esper's Agency (o so Itsuki told Kyon - you can't really believe anything he says). I doubt the author himself knows (or cares) about the real nature of that power.
It is the simple sheer accumulation of weird stuff that Kyon finds preposterous or aggravating but that would make perfect sense for Haruhi that makes clear that she is the source of it.
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It is the simple sheer accumulation of weird stuff that Kyon finds preposterous or aggravating but that would make perfect sense for Haruhi that makes clear that she is the source of it.
NN