Plato’s conversation with the Egyptian priest was hindered by a language barrier which was the source of the confusion. Troy was the son of Atlantia in mythology. The straits the Egyptian referred to were probably the Dardanelles not Gibraltar as Plato assumed. At the time in question, the Dardanelles were within the reach of navel possibly but Gibraltar most certainly was not.

Lots of other interesting connections which don’t come to my mind right now. But I also think Plato figured it out and realized the error and that’s why he never finished the story about it. He just drops the whole thing mid way.