I mostly agree, but with two caveats. We do actually know that ‘neural networks’ are poor models for the brain. Backpropagation is unphysical and brains aren't

I mostly agree, but with two caveats. We do actually know that ‘neural networks’ are poor models for the brain. Backpropagation is unphysical and brains aren't acyclic graphs, for example. What there's uncertainty about is the degree by which they share principles. A glider and an eagle are pretty darn different, and a glider is a terrible model of an eagle, but they do at least utilize the same laws of fluid dynamics to fly. So the question holds for neural networks. As to neuropreservation, it's important to note that we don't need to understand the brain in order for it to be a good idea. What we care about is whether there will be a future wherein someone does, and whether the technique preserves enough mental structure to allow the brain to be recovered by that somebody.