Of course, just from the perspective of English word formation, "-naut" started out taking from "sailor" the idea of "someone who travels amongst" and hence astronaut.
Words like Djangonaut and Kubernaut are taking it a little further, no longer making reference to "travel" so much as just someone who "works with" or "uses".
So "kubernaut" makes sense as "someone who works with kubernetes" as long as you stop thinking of what "kubernetes" means in Greek and (rightly) analyze it as an English word referencing to a piece of software.