I'm reminded of Nick Bostrom's story called "The Dragon Tyrant"[0][1] and David Foster Wallace's "This is Water"[2]. The dragon became so normal in our lives that we do not even question it, like a fish does not question what water is. That we've created a society around this how to deal with this inevitability. But at the end of the day if we could, killing the dragon would be more beneficial and reduce harm by a significant amount.
I see several people in this thread complaining about the economic analysis here or how old people are messing up our world and thus we should fix those things first. For the former question, I see this analysis as adding ammunition to the debate, because many people that determine where we should fund base their decisions on economics. This paper isn't aimed at you, it is aimed at them (speak to your audience). For the latter, I question the premise. Culture has moved too fast that it cannot be purely explained by younger generations dictating the change. This also falls counter to old people controlling everything. So I don't buy the premise. The truth is that if people were living to a thousand years old that society would fundamentally change. Who we consider children and adults would fundamentally change. The truth is that we don't know what this society will look like until we open the box, and until the dust settles. We should be questioning if this is good or bad (we should challenge all ideas) but we need to recognize that this would be such a fundamental change in society that we have no real baseline for determining how we would change. My personal belief is that we do not go quiet into that dark night. There is a lot to fear, but often our fears are irrational. This would save billions of lives, and so I believe it is worth the risk and worth the hardship we will face as society transitions into this new paradigm.
[0]https://nickbostrom.com/fable/dragon.html
[1](Animated by CGP Grey) https://www.youtube.com/watch?v=cZYNADOHhVY
[2] https://www.youtube.com/watch?v=eC7xzavzEKY