It's important for the PM to be on the world stage as well as at home.
In my opinion he's doing bloody well. He's stood up at the UN and announced an emissions target, and recognized a Palestinian state, two things that the USA are going exactly the wrong way on. Plus he still managed to keep the orange buffoon on side and organized a face to face with him, the lack of which the LNP has been bitching about non-stop.
At the moment Australia is looking like a sensible, mature and trustworthy country, unlike several others.