Yeah this isn't the "secret origin revealed" because the origins behind the designs are actually well known and documented. C-3PO was inspired by the robot from the film Metroplis and Vader was a combination of various elements from a WWII Nazi helmet to a Japanese Samurai helmet with the whole breathing apparatus being a design borne from a scene in the script where Vader passes from one ship (the star destroyer) to another (the rebel blockade runner) and the artist (Ralph McQuarrie) thinking he'd need some breathing apparatus to survive in the vacuum (of course in the final film they attached via a sealed airlock).
Certainly there is the possibility that these masks were seen by McQuarrie and Joe Johnson when designing Star Wars and influenced the final look but it's never been mentioned anywhere else before by said designers.
Certainly there is the possibility that these masks were seen by McQuarrie and Joe Johnson when designing Star Wars and influenced the final look but it's never been mentioned anywhere else before by said designers.