In this essay I argue the following:
Brain emulation requires enormous computing power; enormous computing power requires further progression of Moore’s law; further Moore’s law relies on large-scale production of cheap processors in ever more-advanced chip fabs; cutting-edge chip fabs are both expensive and vulnerable to state actors (but not non-state actors such as terrorists). Therefore: the advent of brain emulation can be delayed by global regulation of chip fabs.
Full essay: http://www.gwern.net/Slowing%20Moore%27s%20Law
Sure - but again, it looks as though that will mostly be relatively insignificant and happen too late. We should still do it. It won't prevent a transition to engineered machine intelligence, though it might smooth the transition a little.
As I argue in my Against Whole Brain Emulation essay the idea is more wishful thinking and marketing than anything else.
Whole brain emulation as a P.R. exercise is a pretty stomach-churing idea from my perspective - but that does seem to be what is happening.
Possibly biotechnology will result in nanotechnological computing substrates. However, that seems to be a bit different from "whole brain emulation".
People like Kurzweil (who doesn't think that WBE will come first) may talk about it in the context of "we will merge with the machines, they won't be an alien outgroup" as a P.R. exercise to make AI less scary. Some people also talk about whole brain emulation as an easy-to-explain loose upper bound on AI difficulty. But people like Robin Hanson who argue that WBE will come first do not give any indications of being engaged in PR, aside from their disagreement with you on the difficulty of theoretical advances in AI and so forth.