I’d stake a nontrivial percentage of my net worth on ‘sorry, no nerd rapture, even for the corpsicles’; but I don’t know that we actually know enough about the brain to say for certain. Thanks to lesion studies, we have a (modestly) good sense of what catastrophic damage to localized areas does, and with various degenerative conditions we know, at varying levels of detail, that some widespread but relatively subtle changes are Bad; but ‘people who suffer no localized massive damage but increasingly serious subtle damage across their entire nervous system’ are a test group that has, to date, been notably unhelpful about waking up so we can study them.
Assuming biotechnology/nanites/stem cells indistinguishable from handwaving, you grew that nervous system once, so I don’t see why you can’t grow a replacement; but unless the neural structure that made you ‘you’ is in storage somewhere, it’s overwhelmingly more likely that you’ll regrow a functional, human-spec, but not particularly ‘you’ nervous system.
It’s like trying to restore a bit-rotted medium. You want the damaged file to be restored to full compliance with whatever format it used to be? No problem, we have the spec and the technology. You want it to be the same as it was before? Well, that’s a brute-force search of nigh-unimaginable size through a massive set of candidates, and with no way of identifying when we’ve hit the right one. Good. Luck. With. That.
The only hope for the freezer squad is that, (contrary to what things like ‘major personality changes, usually for the worse, from blast injuries you can only detect with specialized microscopy’ would suggest), ‘you-ness’ is actually remarkably stable, and an extraordinarily large percentage of the possible reconstructions of a somewhat damaged system lead to an acceptably close outcome.
