I don't think this really holds up. They could offer the American engineers the opportunity to move divisions, but they don't because what they really want to do is what they did do: Fire Americans and hire foreigners.
> Will people really come to the US on a H1B if they know they can get scaled down like a cloud server at the first sign of economic trouble or the first sign that some politician wants some brownie points?
Then make H1B what it is supposed to be for: elite specialists, not infinite low cost non-American laborers. Then you won't even need to have this discussion.