The abstract of that article does nothing to support the claim that any Australian languages are originally from India.

You're right! The only sentence about India:

>An expansion [ of the family from the Gulf of Carpentaria] at this time is consistent with evidence from early genetic studies for gene flow into Australia from India ~4–5 ka21, but more recent work has called these findings into question

It doesn't talk about Indian languages specifically. The Gulf of Carpentaria is on the Australian side of the gulf between Australia and Indonesia.

it seems the theory is more disputed than i remember, so lets say around 5000 years ago there was perhaps significant indian introgression into aborginal genetics (as per article above), the introduction of new tools, the arrival of the dingo (speculated by some to be introduced by these indian peoples) and the spread of this language family from a small progenitor language to the dominant language on the continent. So something significant was happening at that time. There are other hints there couldve been previous waves of new peoples from art and so on (these are disputed, from memory). The story of the aboriginals will wind up being more complex and interesting than "showed up 60,000 years ago and were unchanged until the first fleet".

> and the spread of this language family from a small progenitor language to the dominant language on the continent

I was with you up until this point. Do you have a source for this?

Well it is dominant in that >300/~400 languages are bow in this family. This paper argues for a mid-holocene origin from a proto language around the time we are discussing, and also mentions some other theories w sources (https://langev.com/pdf/442ac40068c1d8a67a561d0d7f0fcd95c429c...)