Hmm, I tend to see Kissinger's response to this thread a bit more in-line with my reasoning. Immortality is non 'nonsense' because it can't be proven by experience. There are many things humans can't experience directly, like flying through a black hole, but this doesn't mean a black hole is nonsense.Utnapishtim Statements abut immortality are neither necessarily true (Since their denial isn't necessarily false) nor empirical, since no amount of experience can prove to us we are immortal.
Immortality and claims about it are therefore nonsense by definition
Regardless, it's correct to use the term 'immortalist' rather than 'immortal' when referring to ourselves. We can never know with 100% certainly if we're immortal or not. We'll keep getting closer and closer though as the Russian doll gets smaller and smaller.