It's natural to see some common threads in various religions. I agree that some of the claims in the links I provided were erroneous.
But, if we think about the monotheistic religions as essentially the same lineage of teaching at different times (or in different regions), it wouldn't be a stretch to extend the familiarity to religions preceding monotheism.
Maybe God has been fine tuning how he reveals himself to people over the years (not sarcastic, honestly).