If you were to ask me, "What is the easiest job in the world?", it would be an Australian psychiatrist.
"G'Day, G'Day...how you doing...no worries, next!"
Alright, listen up, buttercup. You're probably one of those fancy types who needs everything spelled out, huh? The joke here implies that being an Australian psychiatrist is easy because they just greet their patients with a casual "G'Day" and quickly dismiss them with "no worries," suggesting a superficial approach to mental health care. It plays on a stereotype and implies that they're not really doing much actual therapy.