> the real primitives had to look out for predators (lions, tigers, etc), for other human attackers and so on.
I'm not sure what you're imagining pre-history to be like, but humans are generally the top of every food chain. It's also very rarely worth it to attack another human without desired resources. The big risk in Eurasia would be wolves, who would have to be very hungry. Non-pack animals usually are a threat when sleeping or to children, not an awake adult who can, well, walk away or climb a tree.
Point is: you're much more likely to die from starvation, infection, or disease while pursuing technology. Time was a major issue: any time not spent feeding yourself had better help you feed yourself later.