I can imagine aging being a technically solvable problem and maybe some of us will live to see it.
But if people didn't age, then there would still be a base rate of mortality from illness and accidents, and so for any arbitrary probability (99.9%, etc) there would be a maximum age that one could reasonably expect to live to.
For instance, if the only thing people ever died of was car accidents, at a rate of 20 per 100,000 people per year, then it would still be very unlikely for anyone to live more than 20,000 years. That's a long time, but it's not millions or billions of years, much less eternity.
Furthermore, if nothing but accidents killed people we might become extremely conservative and do practically nothing for thousands of years. Do I want to use the stairs and risk 99% of my potential lifespan?
So maybe one could say that biology and even physics don't ensure death, probability does.
But if people didn't age, then there would still be a base rate of mortality from illness and accidents, and so for any arbitrary probability (99.9%, etc) there would be a maximum age that one could reasonably expect to live to.
For instance, if the only thing people ever died of was car accidents, at a rate of 20 per 100,000 people per year, then it would still be very unlikely for anyone to live more than 20,000 years. That's a long time, but it's not millions or billions of years, much less eternity.
Furthermore, if nothing but accidents killed people we might become extremely conservative and do practically nothing for thousands of years. Do I want to use the stairs and risk 99% of my potential lifespan?
So maybe one could say that biology and even physics don't ensure death, probability does.