Probably. A lot of ancient civilizations have stories about major floods, which isn’t surprising given that those same civilizations all lived alongside large bodies of water prone to flooding. All it takes is for one catastrophic flood to be talked about generation after generation, growing larger and more severe in each retelling until it was eventually recorded as the stuff of legends when writing was invented. Alternatively, stories about several different floods could have been combined over time into a tale of one mega-flood. Anyone who lived through the Great Blizzard of 1993 should be familiar with how this works. Even with photos, videos, and scientific data about the storm’s actual portions, plenty of people still exaggerate how big it was. And they sometimes conflate it with other major blizzards (which is easy to do in the Northeast given how many blizzards they get).