As things stand, this is what happens to a human family in a nutshell. Two people start dating. If things go well, they may want to live together and have kids. The kids grow up and do the same, eventually, and the original parents become grandparents, generally around the time they start being elderly. Unfortunately, this means they are less and less able to take care of themselves (let alone their grandchildren), and thus are more of a burden than a helping hand. (Talk to people who are around 60 and have kids, and you’ll find out their worst concern is being a burden to their families the moment they’re no longer able to take care of themselves.)
Grandparents eventually die. Repeat the process for enough generations, and eventually the members of the original family will all have died—the family is dismantled. Maybe other families originated from it, but it is irrelevant. The people are what matters to us, not their genes. Genes will be passed on, but all the people in the process will die, and become just a carrier for the genes. Looks like we really should have read the fine print before signing up for life, eh?
On the other hand, here’s what would happen in a post-rejuvenation world. Two people start dating. If things go well, they may want to live together and have kids. The kids grow up and do the same, eventually; the original parents become grandparents, but whether this happens in their 60’s, 90’s, or 120’s is completely irrelevant. Biologically speaking, the grandparents look and feel 25-30 years old, although their chronological age is over 60. Their health and energy does not diminish as a function of time, and rather than becoming a burden on their kids, they’re actually able to help and make things easier for everyone, including themselves. While growing up, kids won’t ever have, in principle, to worry about how grandpa is getting sick and how he’ll eventually die. Grandpa is alive and kicking all year round. Grandpa and grandma will live in the prime of health long enough to see their own grandchildren have kids, just like the children’s parents will. Maybe grandpa and grandma will split one day, because while people can be rejuvenated, sometimes feelings just can’t. Instead of dying sick and lonely, grandpa and grandma can have a new life. They aren’t forced to stay together because they’re too old for all the troubles of a divorce. Maybe they’ll want to be with someone else, or maybe they plan on being single for the next 20 years and dedicate themselves to acrobatic parachuting and space exploration, respectively, just because they are that awesome. Eventually, they can still go and see their nephews, grandnephews, and grandgrandnephews, even though they are not together any more. I’m sure you agree all of this would be a bit difficult to do if grandpa and grandma were dead.
TL;DR: Ageing and death wipe out families. Rejuvenation would help keep them together, and even when they fall apart, members can still see each other if they wish.
Me? Personally, I’d be pleased to see my dad again 20 years from now, in the prime of health, rather than seeing him wilt and die. I’d gladly meet his new family if he created a new one. Same goes for my mum.
What do you wish for your parents? And what about your kids? Would you like them to have to see you rot in a hospital bed, or to go all together for a picnic to celebrate your 120th birthday? If you actually had the choice, would you really choose ageing and death? And if so, in the name of what? Think carefully.
Objections to rejuvenation
Objections to living ‘forever’
All answers in short