Is three-score and ten the limit?

Johnathan Pearce discusses the implicit biases against life extension:

Considering how many health-scare news items there are these days, it makes me want to smile in a wry way when I also read about the supposed problems caused by an ageing, greying, population. The first and obvious question is: if we are all at such risk from obesity, drugs, booze, stress, pollution or the angst of watching Jonathan Ross, why are we living so much longer than our parents or grandparents? If this is what happens when the sky is supposedly always about to fall in, then what must a healthy population be like? And yet there is something in the human psyche, or our culture, that rebels against the happy prospect of a longer life. We are told, or at least have until recently accepted, that three-score years and ten is Man's rightful due (perhaps a tad longer for women); it is almost a hangover from religion to believe that it is impious, even blasphemous, to want to live for much longer. Andrew O'Hagan, writing in the Daily Telegraph today in a moan about how the elderly are treated in Britain — a valid subject — makes this point:

Growing old is now considered more of an option than an inevitability, something to beat rather than be resigned to, something that is thought to take away from one's individuality rather than deepen it.

I don't really know how death, or its inevitability, adds to one's individuality. I think I know what O'Hagan is trying to say: We are unique, precisely because we are mortal. We cannot be replaced, or copied.

The trouble, though, is that I don't see how one's uniqueness is somehow reduced by living for 200 years rather than say, 100, or 50, or 30. Were the ancient Romans — average lifespan about 35 — more individualistic and unique than a 21st Century Brit? How on earth can one measure this? Also, the desire to keep the Grim Reaper at bay surely attests to a love of life, not a denial of its value; if one believed in a craven acceptance of the inevitable, then why do we have doctors and hospitals?