They didnt mention that a lot of Australians go overseas to work for companies, which could be a boon for us if an ecosystem blooms here, as I know a lot of entrepreneurs would love to move back to australia for the lifestyle.
I think he is vastly overestimating the number of Australians over here.
I'm one of those Australians who moved to the US to work at Google, and then left to join a startup, Puppet Labs.
There are a lot of Australians in tech in the Bay Area, particularly working in operations, and a regular topic of conversation is "what would I do if I moved back to Australia?"
I'd still probably try to start a new tech company in the US, but I feel much less strongly about that than I did a couple of years ago, and hopefully that trend continues.