There's one thing that doesn't quite add up. If a gradual loss of seafaring technology was the reason for the islanders' isolation then the people on the African coast must have lost that technology as well. Otherwise people would have continued to travel from Africa and reintroduce the technology to the islands.
It seems extremely unlikely that the technology was gradually and seperately lost on both sides.
It seems extremely unlikely that the technology was gradually and seperately lost on both sides.