The most obvious problem with this article is that it assumes Von Däniken came up with this idea. Years before "Chariots of the Gods", Peter Kolosimo already had best-selling works discussing ancient aliens.
https://rationalwiki.org/wiki/Ancient_astronauts
"However, the fifties and sixties were more dominated by European works. The Italian Peter Kolosimo wrote several books as early as 1957, but his Timeless Earth (1964) became an international best seller and was translated into several languages. French-language authors included Henri Lhote who proposed that prehistoric Saharan rock art depicted close encounters, Bergier and Pauwels' Morning of the Magicians (1960), Robert Charroux's One Hundred Thousand Years of Man's Unknown History (1963) and Misraki's Flying Saucers Through The Ages. A few British authors also published before Von Däniken, such as Brinsley Le Poer Trench, John Michell and W. Raymond Drake who wrote Gods or Spacemen? in 1964.
"Although Von Däniken claims he was formulating his ancient astronaut ideas throughout his school days, it is clear that many others had already published their books on the subject, long before he became notable with Chariots of the Gods? in 1968."
Your precedence note is fair but it seems likely the whole "ancient aliens" subject was in the air around that time; pseudohistory has existed as long as history and this particular strand just emerges with the sci-fi boom and particularly the post-war fascination with UFOs.
Von Daniken was obviously just particularly good at pushing his brand of the nonsense; all of those authors though are interesting examples of the sort of anti-academic and conspiracy theorists that have reached their apogee in recent years via social media.
Good point. I was introduced to the idea that aliens came to earth long ago and invented humans and built lots of weird monuments through The Mountains of Maddness by H P Lovecraft, written in 1930.