What is the point at which these giants collectively tell us to fuck ourselves and run off to the Chinese nirvana you describe? Is it just north of where we are already, so if we don't get some immigration relief immediately we're all doomed?
Maybe. Or maybe the whole process isn't as clean as you're implying that it is. I do know that for as long as I've been paying attention a standard Republican refrain has been that if we don't lower our taxes to zero then all industries, in their game-theoretic wisdom, will evaporate from our lands. And yet businesses keep failing to migrate en masse to whichever Dakota has no taxes, and Minnesotan industry draws another day's breath.
To reiterate, I'm not saying you're wrong; but the causal chain is considerably more entropic than you or pg are letting on.
Disclosure: I'm an American who has worked for Microsoft in Beijing for 7+ years.