I think the "current" commercial freezing methods offered are a sham. With companies basically only offering hope to those in a desperate and dire situation.
The brain is such a delicate thing, that even minor changes physically as well as chemically can have massive effects on someone's personality. And that is to somebody who is technically fit and well. It is my belief that most people "currently" frozen have zero chance of being revived, especially in respect of being the person they were at death.
I think the only good thing happening, is that at least some data will come out of it for superior methods of doing it properly in the future.
I think the main problem in any future revival will entirely depend on the method and timings that the body is frozen at the moment.
As most medical people will know, anybody suffering from Cardiac arrest will only have a certain time before oxygen starvation starts to damage the brain.
As already understood, once brain damage has occurred, certain memories and that persons personality will be gone. To what degree depends on the length of starvation.
So while the person may recover bodily, the brain may not. Even with massively advance technologies in the future that can revive people and fix the brain to a functioning state, the hard bit will be restoring the person or personality (ie their data). If that "data" has gone through oxygen starvation before freezing, people in the future will have nothing to go on how to fix or restore it.
Waiting for somebody to clinically die, ie heartbeat to stop, may have already caused massive damage to the brain. I believe brain activity carries on for some time after cardiac arrest, so actual brain death will occur some time after. Time is the factor and what can be done to stop oxygen starvation and damaging ice forming during freezing.
So the best method would be to induce a coma before death, introduce chemicals to the bloodstream to prevent ice forming and oxygen starvation. Then lower the body temperature as best as possible to help with both.
I believe current laws do not allow this, as it would be considered either assisted suicide or even murder. If we are to carry on with this, then the law needs to change to allow it to be done properly to give these people a chance in the future.
I would love to see the future, who wouldn't? But i believe people should except that death is a part of life and make the most of any time offered. We could end up with entire families deciding to freeze themselves if one falls ill (to await a future cure). This is complete madness, and we are indulging the weak/rich who cannot face death. We could end up with future generations all opting to freeze themselves awaiting advances in technologies that will cure or extend their lives.
Maybe one "out of the box" idea would be to use "speed" to allow people to await the future. It has been proven that the faster you travel relative to another location, time slows for you. So if we could shoot somebody into space, and get them to travel fast enough. Then time here would pass faster in relation to them. If we somehow did it in a giant orbit that would bring them back in two hundred years for example, then it is possible they could have only experienced hours/days. I'm sure a resident "expert" on here could work out the maths to estimate the speed/distance needed etc!