>>18083262
>Yes, but why due East so fast and so directly whilst passing by lots of seemingly good/better environments than Oz.

They didn't. The Negritos of South East Asia are proof of this. Originally the entirety of SEA was inhabited by Andamanese/Onge and Papuan-like hunter gatherers until they got later absorbed by farmer Austroasiatic and Austronesian populations in the neolithic.

In terms of human settlement, hunter-gather generally lose to farmers.