Obviously the VC funds are different, and nowhere near the scale that they are in the US or China right now. Still, there is a lot of wealth in Australia seeking investment opportunities.
It would seem to make perfect sense to stay domestic and contribute to building up the tech scene there.
There are problems with the generalizations in the article though. The author talks about American entrepreneurs being, basically, obsessed with get rich quick schemes, and that outcomes are more binary in the US - that's mostly a Silicon Valley cultural thing. There are tens of thousands of successful tech companies all over the US that have grown themselves slowly, are great businesses, but are not unicorns, and are not an all-or-nothing proposition. Why didn't the author look at other tech start-up cultures in the US as an alternative? Alternatives exist in every major city. I get that, in that scenario, it makes as much sense to stay in Australia - so then why mess with Silicon Valley at all, by now it's pretty blatant what it's all about. That contradiction left me confused.