> Could you say why you think this?

During my time as a medical research minion I did some work on preserving tissue samples and even whole organs, including plastination and similar resin casts. What you need to be aware of is that, while the finished specimen look very good and life-like, they are radically altered on a biochemical level. All the water and lipids get replaced by resin. That requires soaking them in formaldehyde, acetone, and other chemicals before resin can even be applied. This process absolutely destroys proteins, in fact it relies on that. Also, the whole process takes days to complete, and during that time bio matter is actually being washed out and the whole structure is in motion. There is absolutely no question that information is lost here, in droves. If you believe plastination has a decent chance of preserving people's minds, you're operating under the assumption that the connectome itself will yield enough data for an upload.

Compared to that, freezing is, well freezing. Molecular motion almost ceases, so the most important aspect to gauge information loss in cryonics is what happens to the brain until it's finally cooled down. There are three main problems here. The first is the formation and shape of ice crystals which can (and do) destroy cells. This is a bit more relevant to in-vivo reanimation enthusiasts, because the physical shearing should probably be algorithmically correctable in a scan scenario. The second is the effect of the cryo fluid they pump into patients to prevent said ice crystals from forming, because it's also toxic to proteins. It's not as invasive as plastination, but it's still pretty bad. The third aspect is the time span from asystole to the halting of information loss. This might be a problem, but since current research indicates that a lot of ischemic brain damage is actually a cascade triggered by re-perfusion, there is cause for the assumption that anything up to a few hours might actually be fine.

> Were you convinced by the experiments done by the Cryonics Institute or Alcor?

I have to admit to only a passing knowledge of their in-house research efforts. Alcor's that is, I know next to nothing about CI. The problem is, they - nor anyone else for that matter - are not in a position to make any substantive claims about information fidelity beyond the continuing efforts to preserve the brain as faithfully as possible. A lot of their statements seem to focus on future viability of the tissue, and options for biological reanimation - but these are things I have no interest in (because I think it's both unrealistic and a bad deal). In fact, the last time I visited Alcor's site I couldn't find any reference to uploading at all, maybe I just missed it though.

> Political, maybe, if the the legal status of patients changes so that they are required to be thawed.

Yes, I agree. It's a massive taboo, ask any random person on the street and they'll be horrified. It's not difficult to imagine neuropreservation might get outlawed as soon as it looks like it might actually be feasible. In fact, we're seeing the same thing happening now with AGI. One can only imagine the public outcry involving bringing conserved brains back to life will be magnitudes larger than whatever will happen in respect to AGI soon.

> But why economical or technological?

By definition, cryonics companies have to operate on the fringe. That makes them especially vulnerable to disruption from relatively minor events. But even if they were as stable as, say a major bank: well, those fail, too. And if they're not going bankrupt, one might imagine a power outage lasting for months. Or some other infrastructure catastrophe that results in these companies being unable or unwilling to maintain services. Us western countries are kind of operating under the assumption that we're stable and eternal, which is an illusion.

That's why I said it's a solution for the next decades at best. During that time, if we really want to put resources behind it, we could theoretically figure out a destructive scanning -> uploading workflow (simulation can come later in principle). But if we're talking about biological reanimation... there is not even a tenuous time frame imaginable. We could easily talk hundreds of years until our nano tech is sufficiently advanced. And that's too long for two fragile companies to keep afloat in the face of economic crises, religious and cultural disapproval, incompetence and malice, accidents, disasters, and world events - any single one of which can wipe everything out.