I think I'd apply for the position of guy who's super interested in something that's only interesting cause it's gsmeplay relevant. I'd stand by a river staring at it day and night and when the protagonist talks to me I'd say "I'd bet I could use a boat to cross this river."
What I never understood about the NPC thing is that it's always assumed that NPCs are not like other main characters in the story. But it's just any character you can't play right? Even characters who have like hours and hours of screentime showcasing and developing a complex and nuanced personage.
It's just calling someone brainless, a zombie, non-human, except in a stupid new way.
The term (which is deeply reactionary and shouldn't be used except to criticize it) is based on a more literal reading, since NPCs aren't players, i.e. aren't controlled by a human but instead just have scripted dialogue, they don't think and don't have any sort of internality, they just do things automatically. "NPC" is a branch of the weird 4chan incel Discourse of asserting things like "only we have internal monologues, the normies don't" as though not hearing what other people think means that they don't think.
It's a of the peolyou aren't but in this case I think people know what I mean. It's not that deep.