SpaceX is a good example. The number of people who would benefit from such a moonshot-like effort to cure ageing, if it was driven by private entreprise, would be about the same as the number of people who can afford space tourism currently. A privately-developed cure of ageing would be astronomically expensive, indeed.
Oh, I have no doubt that the prices would eventually go down- in like a few hundred years after the cure was invented. Until then the people not able to afford it would still die in droves while a few powerful and affluent people would ascend to a kind of immortality.
Bostrom doesn't even try to think of how a very expensive panacea that cured ageing and all the ailments that came with it would be distributed to a majority of the human population that even now cannot afford basic healthcare to extend their health-span even for a few years.
How is this current state of affairs supposed to be ethical? And how can we ethically justify halting ageing for only a tiny handful of people out of the entire world population?