I can extrapolate based on my toddler that a modern human dumped in the wild would invent language. He has made several phonemes that aren’t in the language we speak at home. And he’s clever enough that even though he’s never seen us stand on furniture, he still climbs drawers and chairs if there’s something he wants that’s out of reach. I think that tool use and language are borne of some innate drive that’s accelerated by culture.