Can’t say for certain if he was right, wrong, or perhaps a bit of both. How does one explain the Nazca Lines and other geoglyphs? Easy enough to make simple straight lines long in length in sand and gravel, but intricate depictions? How others quarried, transported and arranged enormous stones has never been discovered, and in many parts of the world where travel and transport is not simple or easy. Perhaps our ancestors had secrets for moving enormous weights that our shining scientists of today can’t explain, and they did it without help or maybe not. It’s what mysteries do, they make us wonder and I think that’s a good thing.
Back in the late 70s an actual scientist working on the plateau found the models the original artists used and then scaled up. She also noted that the plateau was soft ground and joked that it would make a lousy runway to land on.
Quarrying and transporting stones is and obviously always has been well understood, and that makes the achievements of often apparently illiterate cultures that did it even more awesome.
Drilling stones was accomplished by using small stones with at least the same hardness, and turning or twisting them until the holes got drilled. They had the time, they didn’t have TV, movies, or the internet to distract them.
It’s ironic that in this era of labor-enhancing and time-saving technology we don’t appreciate the collective human genius.