I agree that a future world with currently-existing people still living in it is more valuable than one with an equal number of newly-created people living in it after the currently-existing people died, but to show that cryonics is a utilitarian duty you’d need to show not just that this is a factor but that it’s an important enough factor to outweigh whatever people are sacrificing for cryonics (normalcy capital!). Lots of people are dead already so whether any single person lives to see the future can constitute at most a tiny part of the future’s value.
I agree that a future world with currently-existing people still living in it is more valuable than one with an equal number of newly-created people living in it after the currently-existing people died, but to show that cryonics is a utilitarian duty you’d need to show not just that this is a factor but that it’s an important enough factor to outweigh whatever people are sacrificing for cryonics (normalcy capital!). Lots of people are dead already so whether any single person lives to see the future can constitute at most a tiny part of the future’s value.