Your thinking - IMO - is affected by your experience with your grandfather, and I can understand that. But consider that for many people, myself included, the thought of dying in the future is a burden (not THAT big, in my case, but it's there) that we carry with us for a large part of our lives. On top of that there is the thought of our parents, spouses etc dying before us. I think that sucks more than the chance of life prolonging medicine going wrong. You know, VERY few people actually want to die even when they are debilitated by old age.

I don't want to have to die, and I don't want other people to have to die either. I would be delighted to spend as long as it takes solving the overpopulation problem once the problem of dying is dealt with.