The risk to people in Australia is low if the returning people,...

The risk to people in Australia is low if the returning people, from whatever country, are placed in quarantine for the designated amount of time required by our health experts, in order to make sure they are virus-free on release. That time could be extended to cover unusual cases like India, where the variant is not fully understood. Note that I said the risk is "low", not zero. There is no certainty with anything to do with Covid.

By your logic, we should also deny lung cancer treatments to smokers, as they likely brought on their own condition. I hope you're never in the same situation of needing help and not getting it because it's deemed that you "brought it on yourself". You sound as selfish as you regard those Australians stuck in India.