its a lot less than 1% chance. right now its a 0% chance as it's not known it would ever be possible. its an assumption that, given we've done so well at medicine that past 50 years or so, we might be able to do something at an indeterminate point in the future. reality is it may never be possible to regenerate a dead brain, we dont even know how or what happens to the brain in death. we struggle to understand the mechanics in living.
Well, quite. And yet.... my grandmother was born before the Wright brothers flew...and died having witnessed man on the moon, rovers on Mars, the eradication of Smallpox, heart transplants etc. The rate of progress in the scientific, technological and engineering disciplines in the last century has been simply stunning, and, in most areas, the pace of change is accelerating still. So, imo, it's not impossible that at some point it may, just may, be possible to revive a cryogenically frozen body. It wouldn't be a choice I'd make, but I can see why someone might take that chance - after all, given the alternative, what's there to lose if you have the money?