As for generalisations of broad groups of people - any attempted generalisation on observed phenomena will automatically be false, but saying that you can't make generalisations on phenomena because they are not absolutely true is throwing the baby out with the bathwater. What I said was not a value judgement, and not an attempt at "psychoanalysis-at-a-distance" but my current assessment based on what I've learned so far about people and life. It could very well be false. Also, I'm no exception. Had I access to a magic pill that would be able to prolong a healthy life for my loved ones and myself as much as we want, I'd not hesitate to take it (as I think most people probably would), but I have a feeling there is a higher level of happiness one can seek than extending one's life indefinitely.
Regardless of whatever finite amount of time you have, can the best way to spend it be pining for more?
Also, psychoanalysis-at-a-distance of broad groups of people is generally awful, even when the broad groups of people are unusual. Please don't.
Also, unbounded lifespan isn't the same as irreversible immortality. Irreversible immortality, assuming you can implement it somehow, seems like a sort of bad idea.