I cannot even imagine suffering 50 years at Guantanamo Bay. Is 20 potential years of freedom after 50 years in Guantanamo Bay worth enduring? Probably not, at least to me. Is there a point at which 50 years in Guantanamo Bay becomes worthwhile? Probably. I don't know exactly where that point is, but I know that it exists (e.g., 1000 yrs of satisfying life is worth it, but is 100?).

Given the human failures, "unsolvable" is usually a mistake, especially when you can expect more than two decades of lifetime.

I agree completely. This is even more obvious when you postulate life-extending technology. However, this still does not change the fact that death is not the absolute worst thing, which was my point (however well I communicated that).