Australia has an order of magnitude fewer people, has a different regulatory environment (e.g. their counter-terrorism bill that lets them coerce engineers into

Australia has an order of magnitude fewer people, has a different regulatory environment (e.g. their counter-terrorism bill that lets them coerce engineers into cooperation, and in the wake of the NZ shooting they're proposing to imprison website operates that don't take down content quickly enough - and apparently 90 minutes isn't quick enough) and is located in completely different region of the world. There are plenty of reasons why one would want to move to the US but not Australia.