Frank Herbert had unlimited freedom to fantasize about Dune. It was an imaginary Sci-Fi world on planets which he invented. Ayn Rand wrote about a future United States in which railroads are the main source of transportation, oil from a single field in Colorado is critical to the entire economy, an inventor who created an engine that runs on static electricity all by himself was driven into exile, a crucial Chilean coppermine existed near Santiago and belonged to a guy with the name of the Ancona, an Italian ship that sank in WWI, and some guy invented a mysterious special blue metal stronger than steel.
The original story was a mashup of stories about Nicola Tesla, petroleum production and fantasy railroad speculation that was somewhat silly in 1950, but was absurd when set in modern times. And then there is John Galt's 56 page radio speech (there were no TV's in Rand's future world: no one who writes for films - and Rand did know about screenplays- puts hour long rants into a novel intended to be made into a film). There was no way to make the story even minimally credible.
Rand's cardboard novel characters are equally cardboardy in all three (3!) casts of this series.
Herbert's Dune was sort of a mashup of the origins of Islam, as though a desert society would naturally resemble that of the Arabian peninsula. But his creativity with regard to technology (mentats, adepts, tiny poisonous drones) were more in keeping with the society in which they exist.
