This means you have to have hunter-gatherers hanging around the Mediterranean at about 9600 BC to observe events, and they have to be rowing out in canoes (if not Atlantean helicopters) in order to be familiar with the alleged drowned island, and then pass on the history through thousands of years of verbal tradition to the pre-dynastic ancient Egyptians, who can (much later) tell the Greeks. It's possible, but an alternative explanation is no.
Göbekli Tepe is direct evidence of an advanced society over 11k years ago.
Humans are story tellers. Stories last a long time. The youngest fossils of Megalania, which grew up to 7 meters (23 feet) in length and weighing over 600 kg (1,300 lbs), which is the largest terrestrial lizard known to have ever lived, date to around 50,000 years ago, confirming that it was alive when the first Aboriginal people arrived in Australia. Early human inhabitants and the giant lizards would have shared the same environment, and Aboriginal oral traditions about giant goannas may be based on these ancient encounters.
That's an interesting thing, but all the same, Plato's myths aren't history in any sense, and mistaking them for that is not an error of degree but of type.
What happened to the "may"? So the story is about the "Whowie". It says here it also had six legs and the head of a frog. Based on a true story, maybe.
Do you have a suspect for the Bunyip, by the way? I like that one.