Denying that cryonics is relevant or useful or a valid area of research and development because no-one has yet completely implemented the full loop of technologies for reversible full body cryopreservation is missing the point. (But note that it has been done for a single organ, which was transplanted, and functioned).
The point is that we could be saving lives, and we are not, largely because of irrational objections that are not really based on technological or scientific positions, but grasp at a those positions as a shield for the real nebulous feelings on the matter.
The reversal of cryonics in the future has been written on extensively. There are very detailed treatments of what would be required. There is no sound reason to think it impossible; it's just a matter of sufficient control over chemistry and biochemistry. If you believe that there is some sound reason that it is impossible, then publish a paper - it would be influential if correct, because it would demolish the work of much of the cryobiology community in their initiatives to create reversible cryopreservation of organs and tissues.
Here is the paper for this research by 21st Century Medicine: "Aldehyde-stabilized cryopreservation":