The Bible is not a scientific textbook. It is a book that teaches people spiritual truths, not scientific facts.
So you and I agree there was no Great Flood as described in Genesis, and that the bible contains folktales presented as facts, then?
There would be no point in turning to scientific texts for spiritual answers, correct?
On the contrary, I think the study of humans and how they think is capable of greatly illuminating why virtually all of them/us have invented gods at some time or another.
As you'll have noticed, in the early part of the Tanakh, it's taken for granted that there are many gods, as shown (amongst many examples) in the command,
Thou shalt have no other gods before me ─ instead of
Ain't no other gods! That's called henotheism, as you doubtless know. God only becomes the sole God after the Babylonian captivity, say by Isaiah.
And of course God continues to evolve. The Christian version of [him] splits off in the first century CE, renounces the covenant of circumcision, shifts the seventh day to Sunday, and as a matter of political necessity adopts the Trinity notion and thus officially raises Jesus to God status around the 4th century, though the pressure had been there since the 2nd century.
Then the Christian God splits into east and west, then the west splits into Catholic and Protestant, then the Protestant splits into high and low, then the low fragments split into literally thousands of pieces. We also find Jesus in the Mormon church and the Rastafarian church.
So the effort of a bit of study is well repaid with some understanding.