Genesis attributes the flood to human sin (6:5-7), not overpopulation, as Atrahasis’ Epic and the Greek poem Cypria did and not unlike the pagans who repeat it today. It just might be where they got the idea along with their Gaia godess et al.
I’m not quite sure how this threads with my reply. I’ve made no mention of overpopulation. Any attribution as to cause of the flood in Greek, pagan or other beliefs would necessarily follow the point of view of the fallen angels and their progeny, under this interpretation, so it stands to reason that it conflicts with Genesis at base but contains certain broad themes that are remarkably similar. It would have been a matter of perspective.