Good futurology is different from storytelling in that it tries to make as few assumptions as possible. How many assumptions do we need to allow cryonics to work? Well, a lot.

• The true point of no return has to be indeed much later than we believe it to be now. (Besides does it even exist at all? Maybe a super-advanced civilization can collect enough information to backtrack every single process in the universe down to the point of one's death. Or maybe not)

• Our vitrification technology is not a secure erase procedure. Pharaohs also thought that their mummification technology is not a secure erase procedure. Even though we have orders of magnitude more evidence to believe we're not mistaken this time, ultimately, it's the experiment that judges.

• Timeless identity is correct, and it's you rather than your copy that wakes up.

• We will figure brain scanning.

• We will figure brain simulation.

• Alternatively, we will figure nanites, and a way to make them work through the ice.

• We will figure all that sooner than the expected time of the brain being destroyed by: slow crystal formation; power outages; earthquakes; terrorist attacks; meteor strikes; going bankrupt; economy collapse; nuclear war; unfriendly AI, etc. That's similar to the longevity escape velocity, although slower: to survive, you don't just have to advance technologies, you have to advance them fast enough.

All that combined, the probability of working out is really darn low. Yes, it is much better than zero, but still low. If I were to play Russian roulette, I would be happy to learn that instead of six bullets I'm playing with five. However, this relief would not stop me from being extremely motivated to remove even more bullets from the cylinder.

The reason why the belief in afterlife is not just neutral but harmful for modern people is that it demotivates them from doing immortality research. Dying is sure scary, we won't truly die, so problem solved, let's do something else. And I'm worried about cryonics becoming this kind of a comforting story for transhumanists. Yes, actually removing one bullet from the cylinder is much much better than hoping that Superman will appear in the last moment, and stop the bullet. But stopping after removing just one bullet isn't a good idea either. Some amount of resources are devoted to the conventional longevity research, but as far as I understand, we're not hoping to achieve the longevity escape velocity for currently living people, especially adults. Cryonics appear to be our only chance to avoid death, and I would be extremely motivated to try to make our only chance as high as we can possibly make it. And I don't think we're trying hard.