If we could “upload” or roughly simulate any brain, it should be that of C. elegans. Yet even with the full connectome in hand, a static model of this network of connections lacks most of the information necessary to simulate the mind of the worm. In short, brain activity cannot be inferred from synaptic neuroanatomy.

Straw man. Connectonomics is relevant to trying to explain the concept of uploading to the lay-man. Few cryonics proponents actually believe it's all you need to know to reconstruct the brain.

The features of your neurons (and other cells) and synapses that make you “you” are not generic. The vast array of subtle chemical modifications, states of gene regulation, and subcellular distributions of molecular complexes are all part of the dynamic flux of a living brain. These things are not details that average out in a large nervous system; rather, they are the very things that engrams (the physical constituents of memories) are made of.

The fact that someone can be dead for several hours and then be resuscitated, or have their brain substantially heated or cooled without dying, puts a theoretical limit on how sensitive your long-term brain state can possibly be to these sorts of transient details of brain structure. It seem very likely that long-term identity-related brain state is stored almost entirely in relatively stable neurological structures. I don't think this is particularly controversial, neurobiologically.

While it might be theoretically possible to preserve these features in dead tissue, that certainly is not happening now. The technology to do so, let alone the ability to read this information back out of such a specimen, does not yet exist even in principle. It is this purposeful conflation of what is theoretically conceivable with what is ever practically possible that exploits people’s vulnerability.

This is not, to the best of my knowledge, true, and he offers no evidence for this claim. Cryonics does a very good job of preserving a lot of features of brain tissue. There is some damage done by the cryoprotectants and thermal shearing, but it's specific and well-characterized damage, not total structural disruption. Although I will say that ice crystal formation in the deep brain caused by the no-reflow problem is a serious concern. Whether that's a showstopper depends on how important you think the fine-grained structure of white matter is.

But what is this replica? Is it subjectively “you” or is it a new, separate being? The idea that you can be conscious in two places at the same time defies our intuition. Parsimony suggests that replication will result in two different conscious entities. Simulation, if it were to occur, would result in a new person who is like you but whose conscious experience you don’t have access to.

Bad philosophy on top of bad neuroscience!