Here's a high res picture of the C64 PCB, where you can see the markings on the chips:
https://myoldcomputer.nl/wp-content/uploads/2015/11/board-32...You can see both copyright dates, and plenty of other English text. While in 1940 this would have represented incredible futuristic technology, it's pretty obviously made by humans and not a piece of alien magic. It also has components like resistors and capacitors with markings which would have been immediately obvious to 1940s electronics experts.
