The very (alleged) fact that Tasmanians have lost their technology, yet other groups did not, got to be a fairly good indication that Tasmanians were under less pressure to keep it than other groups. The people that came to far north back during ice age, if they lose their technology there, they promptly die. And on a big continent there's large number of other people that'll swiftly get rid of ya if you lose technology.

Also, look at predators: bears, wolf packs, tigers, etc. Vs tasmanian devil and tasmanian 'tiger' which sounds scary but is the size of a dog and doesn't hunt in packs. I'd guess on Mauritius the Dodo coexisted with similar 'predators' that can't eat the Dodo.

Ohh, and the rhetorical questions: hello to the black n white world, where I'd have to prove zero selective pressure in Tasmania. Not interested. It suffices that the pressure is lower and costs aren't. Humans are very unique animals that evolved under immense external pressure. We barely made it. Homo homini lupus est does not cut it for evolving intelligence, or we'd have the original lupus evolving the intelligence. Every predatory species and it's granma are pressuring themselves, and not progressing nearly as fast as humans did, under external pressure, having been forced off trees.