There was a fun running gag in Iron Man (2008) where Agent Coulson keeps calling his organization the Strategic Homeland Intervention, Enforcement and Logistics Division. Pepper Potts says that's quite a mouthful, and he says "I know, we're working on it."
But in Captain Marvel, set in 1995, well before Iron Man took place, Agent Coulson and Nick Fury casually refer to the organization as S.H.I.E.L.D. many times.
Did they use the abbreviation just to simplify things for the audience? Was this a production gaffe? What's going on here?