meaning... a more recent local flood may have caused an author or group to craft an epic about The Big Flood, cannibalizing bits and pieces of older tradition which were folklore concerning the flood at the end of the Ice Age?
makes sense.
impossible to determine either way, but makes sense.
I'm speculating, of course. In Europe and Asia, at least, the stories about the melting of the last ice age would also be intertwined with stories of the flood caused by the Mediterranean eroding through the Bosporus and creating the Black Sea (about 10,000 YA, IIRC).
I think the bottom line is that it's not surprising that Hebrew writers picked up a flood story to include in their creation mythology. There's plenty of real-world material to work with there.