> Most of the top search results and Wikipedia entries tap out on cultures prior to ~5,000-~3,000 B.C.
This is mostly because the evidence that links places to cultures taps out before around 5000BCE. There is of course evidence of large scale settlements prior to that time, but we have little hard evidence about how those map to peoples or cultures, living or extinct, due to lack of artifacts that definitively tie them to a particular culture. After that, we are left with things like projecting population migrations from linguistic evidence.
Perhaps the closest we might find are the remains of 10-30k year old indigenous settlements in Australia, of which we can be fairly confident of at least the set of cultures that produced them.
This is mostly because the evidence that links places to cultures taps out before around 5000BCE. There is of course evidence of large scale settlements prior to that time, but we have little hard evidence about how those map to peoples or cultures, living or extinct, due to lack of artifacts that definitively tie them to a particular culture. After that, we are left with things like projecting population migrations from linguistic evidence.
Perhaps the closest we might find are the remains of 10-30k year old indigenous settlements in Australia, of which we can be fairly confident of at least the set of cultures that produced them.