The percent difference between genomes of species is one of those tricky measures that doesn't really give good intuition. I find it much more useful to think in terms of the time since two species shared a common ancestor.
e.g. For humans and chimps, that's several million years. For Sumatran and Siberian tigers, it's around a hundred thousand years.
So not that far away since modern humans began splitting up into separate subgroups outside of Africa? Of course there have been quite a bit of intermixing since then (more so in Eurasia than the more isolated parts of the world before the modern times, though)
Tasmania may have been isolated for ~8000 years between sea level rise and European contact. But the last person of fully Aboriginal Tasmanian descent likely died in 1905.