In Aaron's first Thor run (the good one) he opens the Gorr story with the statement that all worlds have gods.
As for conflicting creation myths, yeah that doesn't square, except under the "Morrison DC multiverse map" concept where the realm of gods is a place entirely beyond physical dimension where thought and imagination provide the space and time of reality. There, every creation myth is correct because its pantheon believes it is, but every myth is also false because other pantheons believe their own. I suppose, to stick with the Morrison example, the TOAA would be Monitor space, the realm beyond the gods sphere. I dunno exactly how that works with DC because the Monitors aren't magic/divine, they're not gods exactly and don't claim to have created physical reality (I don't think?), just beings from a much much higher dimensional variable.
Perhaps its the connections to mortals that makes a god then.