I hate Aussie cops in general, however, in this instance, I believe the officer is trying to prevent the insane person from spitting in his face. Unfortunately, we have some citizens who are going around spitting at cops, right in the eyes, to deliberately spread COVID19. Right the guy could have absolutely flung her to the floor because she was assaulting a police officer. If it was a man then that would have happened. You’re right to do what you want is no longer a right when it endangers the safety or freedoms of others like she is doing.
There are a lot of comments condemning his actions. Watch the video muted. Forget that she is screaming. What do you see? What I saw was him restraining her without injury and without (from what I can tell) the intention to injure. Even if this is a hoax, or not that serious, or whatever else people might say, if there is a chance, even the tiniest chance, that the small action of covering your mouth and nose might save a single life, isn’t that worth doing?