Facebook has banned specific Australian sites by domain name, so they know in advance the kind of content that is normally published on all the platforms they've banned.

As one of biggest/"smartest" technology companies in the world, they could easily have implemented this response in a way that didn't make them look such bullies.

The laws are very clearly formulated for the benefit of the major media publishers, particularly News Corp and Nine Fairfax, and it would have been trivial for Facebook to limit their ban to those platforms, and perhaps a handful of other large ones that lobbied for the law.

To be clear, I'm not normally in the faction of people hating on Facebook, and generally regard the loudest attacks on them as overblown scapegoating. But, regardless of how technically right they might be, from a PR point of view it's a losing move.