All of the areas that are opened to the public are safe. The main castle structure ruis are currently not safe. Bannerman Castle trust has stabilized the iconic Tower wall with steel braces and has been working on the lower levels to point the feildstone walls. At this time the main castle structure is not safe and can be viewed on a tour 100' from the buildings. the Bannerman Residence has been stabilized and renovated into an educational visitor center. It is safe and open to the public during the guided tours. NY State owns the island and would not sell it.
I asked this question during the tour. It is currently owned and administered by a public trust. It's conceivable the property could be sold, but there are no plans and no current circumstances that suggest any need to do so. A decision to sell would have to overcome public opposition, which would likely be significant.
I highly doubt it but hey, you never know.
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