>>723777086
To be fair, there isn't actual artwork of a Man of Iron, except some mary sue sounding "survivor" named UR-025 and his form isn't probably what they originally looked like.
The God Weapons do look like necrons, but yeah the concept is clearly in reference to the Men of Iron.

40k basically just straight up copied Dune and had it so mankind at their technological peak in fact, created AI and it was extremely powerful. It came to to conclusion however that it was mankind's successor and turned on it then everything got fucked.

Also its implied that the emperor forma de pre emperor wasn't to blame/responsible for this, they specifically wrote that a sub-race of humanity genetically modified to be better suited for warp travel, called the "Men of Stone" decided to create and hand over all their military power to AI.

I can think of no other reason to include this lore bit about a "half-dead" race of spacenoids almost ending humanity than to explain HOW the emperor in all his god-like power would have let robots take over.