Sure, but this is true of neanderthals as well. So we can't say we are especially creative or dynamic in our culture. We can say that our material culture, that small fragment of it that was preserved, was static.

That was the point: I also wouldn't say that about neanderthals.

The evidence on the ground is of course, limited. But it's a fairly common view among anthropologists/archaeologists that our perspective on ancient societies is immensely limited by the material record, hence the generally positive reception to Dawn of Everything despite its sketchy details and interpretations.