True, but the escalation goes in both directions. Google and Facebook are American companies, Australia and the US have existing free-trade agreements. Imposing fines on foreign businesses to force them to roll over for the benefit of local businesses is exactly the sort of thing that free-trade agreements forbid in no unclear terms. There are a lot of factors at play. Trump dislikes Google because the conservative hive mind has turned against it, but favors Facebook because it's supposedly essential to his campaign operations. Plus he's got a protectionist bent and loves trade sanctions.

I doubt that anything will happen, really. It's a negotiation, the Australian government says "give us all your money", Google says "you're not getting one cent" and in the end Google will favor traditional media companies' sites a bit more ("fighting fake news with real information"), donate to a few journalism programs and possibly start creator-ad-share on news.