If dated right, that shit scares me for several reasons.

1. Civilization and technological advances should have happened up to our level or beyond several times which implies there were several collapses, likely due to war.

2. Homo Sapiens might not have been the first or only one developing advance technology, competing cousin species living at the same time might have done as well which also begs the question, who ran the world and who were the slaves. There are myths of ancient gods that ruled the masses, it wouldn't be strange if older pre existing hominid species that had a lower population ruled over the rest that had higher fertility.

3. How bad were those wars that we can't find even the traces of the weapons used nor other clues like ancient satellites or drones, probes or spacecraft remains on the Moon at least.

4. If this has not happened and people just lived in basic hunter gatherer communities, what changed recently that we've become so desperate in forming larger and larger communities and started to invent more things. One would assume a person living 400k years ago simply didn't know as much as we do, but like, was it really that difficult to cultivate plants and raise animals instead of hunting? Why couldn't they make this simple step? It is so baffling, almost as if they were scattered, incredibly small communities that only survived in very biologically diverse regions with lots of food so nobody ever bothered to change the environment and allow only edible plants to grow. Maybe this sort of thinking was akin to magical thinking, like us now talking about colonizing space. How monstrous of a task could have been to clear out the land, keep animals out to not eat the plants or have enough food to feed animals they kept.

Lastly, why did we still discover fourth world tribes as late as the 20th century that lived in such backwards ways as these true ancient people? Was this the main cause for the effect? Lack of contact and communication, exchange of ideas and inventions that held us back? The main trigger for the change was likely the mass migrations out of Africa towards Eurasia and then the Americas and Oceania and then back from Asia towards Europe. Not only that but people out of Africa encountered totally different civilizations created by Neanderthals and other related species in Asia. Did they fight? Did they trade? Did they educate eachother? Did they intermix? Yes, this is what created our modern civilization but why couldn't people have had such migrations before? The oldest building remains we know of that are confirmed are in modern day Turkey and date back to around 10k but there are older structures in Asia that may go back more in time. Who knows how much was grinded down by the sands of the Sahara or buried deep in the soil and forgotten. It's always so fun to think about and ponder, at the very least I think we'll eventually discover much more ancient buildings in Africa under the jungle.