I think even in far limit higher IQ's stones will stay better on the sticks. It ain't easy to attach a stone to a stick well. It isn't some well controlled industrial process here that you can figure out better. One day you have one stick, other day you have other stick. We rely on modelling of reality inside our heads to make items - seeing in mind's eye how it would detach if the wrapping is in that particular place, but would stay on if its in another place.

It's also pretty hard to start fire.

Seriously, I recommend to try without looking up the precise details of techniques. Armed with the knowledge of the fire drill.

Re: tasmanians, once again, it is an island. Birds go flightless on islands just because there's some empty ground animal niche available. We can go complex-tool-less and fire-starting-less on island, too. For the fire starting skill to matter, you got to NEED the fire for survival. In some nearly tropical island, what is the great harm, exactly, in not being able to start the fire? Here you freeze to death in the first winter; there you just eat raw food which is not that much worse anyway. BIG difference in pressure. (also it is altogether possible that they were able to start fire, and it's just racist claims that they weren't)