Atlantis may be a myth, I rule nothing out.
However, to my view, in all probability Plato did not make it up. You can read my analysis on that in this post on my blog: [ourunknownancientpast.blogspot.com]
And consider that in that post I leave out quite a bit. Through the Edfu Building Texts Graham theorizes that the story of Atlantis was known to the Egyptians. He and others present a compelling case for that. Like the book "Atlantis: Egyptian Genesis" which I recently read.