Cryonics is a popular topic among the rationalist community but not the utilitarian community. My impression is that most people who promote Cryonics are generally not utilitarians and most utilitarians do not promote Cryonics.
This seems to be one area where the rationalist and EA communities diverge significantly. My take is that typically those excited in Cryonics are typically in it for somewhat selfish (not in a bad way, just different from utilitarian) reasons, and that there haven't been many attempts to justify it as utilitarian because that wasn't the original intention.
I can imagine some interesting arguments for Cryonics as an effective intervention, but I haven't heard many others give these arguments, and I'm reluctant to steel man a cause for a reason its believers don't care about.
I wanted to open this up for the discussion. I would hope we can roughly come to a consensus on which of the following is true:
1) There is a strong case for cryonics being an effective monetary intervention, and the math has been done to support this.
2) Cryonics can be an effective career intervention for someone with a large amount of career capital in the field, but not for others.
3) There is very little case for cryonics as an effective utilitarian intervention, though it could make sense for other philosophical systems or people with moral uncertainty.
Other questions:
1) If there is no Hedonistic Utilitarian case for Cryonics, are there any strong Effective Altruist cases for it?
2) How much of the above applies to life extension research?
Are you saying that cryonics could improve current people's ability to make long-term investments in the world? I don't see that that's true.
That's actually not what I am saying; rather, I am questioning your claim that human life is exchangeable. Because most people intensely dislike the prospect of death and it makes life a lot more difficult in many ways, it seems much better (to me) to have one person live for 100 years than to have two people live for 50, given the same healthspan.
Separately, I expect that any increased expected chance of an increased lifespan, including cryonics, would increase the average person's propensity to make long-term investments in themselves and in their communities.