I hope that guy gets a lot of beers bought for him as that clip plays over and over in the bars...it was great.
The animal activists as they often do need to get a life and focus on more important things. The dog needed to be rescued. The other animal
was clearly aggressive enough to choke hold the dog. Pretty smart...what's next, instead of Planet of The Apes we get Planet of The Roos?...
As soon as the kangaroo drops the dog he starts bouncing around like a prize fighter and the question is should the guy have just left,
backing up perhaps? Or did he need to persuade the kangaroo to not pursue? Do kangaroos go after you like billy goats, etc?
If they normally leave you alone, which I don't think they always do actually since Youtube has a number of videos with roos punching people,
perhaps all for good reason...

too much aggravation by tourists.
So I think he could have de-escalated, but with that big animal bouncing in front of him like a prize fighter,
a wild animal btw, I think he gets to defend himself. Perhaps he pushed the envelope on that but I didn't see the look in that roo's eye either.