What they should do

Most people who think cryonics work don't sign up. One of the major reasons is that they are worried about reviving in a really bad future, and then not be allowed to die (perhaps for the same reasons that terminally ill people today are not allowed to die no matter how much they're suffering). This includes me. If a cryonics company was willing to let people make conditions for revival, that would resolve a lot of people's concerns and probably reduce cryocrastination. I myself would only sign up if they were willing to do this.

Alcor and C.I. said that they don't think it's an issue because a bad, apathetic world would not put effort into reviving people, and only a good world would. That's not my concern. In an apathetic selfish world I would still probably find life worth living, but my whole life I've suffered so much "benevolence" so horrible that I concluded that "ethics" is what people talk about when they're about to make things worse for everybody. I don't just mean being beaten and other things that society considers wrong; I wasn't beaten (at least not by authority figures) and in fact had an upbringing society considers proper. What I had was worse and in ways that seem likely to worsen with better technology; Our lives were so restricted and full of "structured activities" that school was pretty much the only place we could socialize at all, and there were a whole lot of other problems too. I haven't signed up because I dread the idea of my life continuing, and although there is a reasonable chance that life can be good it wouldn't be worth the risk unless they can agree that I would be allowed to die if I wish it.

 I wrote a draft about my life, and it was just really long, heartbreaking, and goes on and on getting worse. Worst of all, nothing in there was considered abuse, everything in there is common (although I did get an unusually bad case), and society is willing to work hard to ensure it. Did you know that runaway children are required by force of law to be returned to their household? I would have run to a third world country to escape it anyway if I didn't learn that the same modern problems happen there too (such as credential-ism: you even need college degrees to go into most monasteries these days). I won't post it publicly since reading it would mainly cause unproductive pain, although I'll share it with users who say that it might make a difference in cryonics policy.

I would be more comforted if society has been becoming better over time, but that wasn't the case. When settlers on the old frontier joined the Native Americans for a while, they usually went native permanently; the reverse was extremely unlikely. Hunter-gatherer children seem to play all day and learn the extremely complicated skill set needed when everyone does everything themselves by doing so; children today are sent to awful schools that make them dread the thought of math, and rarely even retain the knowledge. Modern countries pride themselves on their humane treatment of prisoners. And by “humane”, I mean “lock them up in a horrible and psychologically traumatizing concrete jail for ten years of being beaten and raped and degraded, sometimes barely even seeing the sun or a green plant for that entire time, then put it on their permanent record so they can never get a good job or interact with normal people ever again when they come out.” The Scandanavian prisons are better than most systems but are also much worse than classic punishments because prisoners must pay for their stay. Which is harsher, 12 hits with a cane and and sometimes a short prison sentence like in Singapore, or a long sentence plus 30,000 hours of unpaid labor? And Dr. Scott Alexander had a whole post on how the medical system treats elders far worse than anything that would have been possible in the past.

I'm not saying that all progress was bad; I'm not running off to join the war of extermination between the Taliban and ISIS either. But transhumanists massively underestimate the amount of bullshit and suffering normal people experience in their normal life, even when things are normal. The local preacher at a nearby church has had a much easier time winning converts by saying "When was the last time you have had hope in the world without it becoming immediately betrayed? All worldly things will fail you, you must turn to Jesus." than transhumanists have had by saying "Isn't life great? Don't you want it to last forever?" And when things are "good" like when someone's getting an "education," things are even worse. There's no way that 1 in 6 kids reporting suicidal ideation and 1 in 12 attempting suicide is remotely healthy. 

On the other hand, things might turn out genuinely excellent and worth living for. I know cryonics would work because fetuses are already regularly preserved for decades before being implanted in the womb by an almost identical "Embryo Cryopreservation", are regularly treated with "clinically induced hypothermia" to avoid brain damage during surgeries, and know from physics that when kinetic energy is low enough that atoms can't move past each other or react. People who were preserved for 2 decades as an embryo then recovered without damage only can grow up thinking that long term cold storage is pseudoscience because humans are insane. It's also cheap enough (life insurance that can pay for it only costs about $30 per month) to be worth considering. If any of the cryonics companies were willing to make an agreement that I would only be revived if they could guarantee my right to die then I'd sign up, and I'd bet that a lot of other people are in a similar situation. Please try to convince a cryonics institute to do this if you can.

(There's a high chance that AI will kill everyone or form a paradise soon enough that this is irrelevant, but I've been very confident in things before for strong reasons and been wrong, so I consider the possibility that humans will continue to rule the universe high enough to plan for).

EDIT AS OF JULY 2023: I am signing up whether I can get this assurance or not now for this reason:

After a long period of seeing incredibly fast AI improvement doing far beyond what humans can do even if growth becomes linear instead of exponential, seeing "safety research" being a name for accelerationist policies instead of safety research, seeing the plan for alignment literally be "we will have an AI do alignment research for us", and biggest of all seeing RLHF make blatant alignment failures over and over (proving that the most advanced methods aren't even close to working) yet continue to still be the standard method, I have been convinced that the chance of alignment success from humans (except for the tiny portion able to notice problems staring them right in the face) has become pretty much zero. (this is good.) 

Superintelligence could become friendly anyway, for the same reason humans changed their utility function almost completely upon reaching the Enlightenment (for example, Augustine and Tertullian said that the greatest pleasure in heaven was watching the torments of the damned, while C.S. Lewis wrote a story about people in heaven taking great efforts to save the damned). This seems likely enough to me that I think it's still worth it to sign up. Laplace's law of succession says that this is 2/3, although I'm not nearly that optimistic; my p(doom) is still about .9. I don't need this assurance from cryonics companies anymore though.