An industry expert telling you that X is the solution to everything, and then years later saying that Y is the solution to everything, without any acknowledgement whatsoever of their previous statement on the subject, is messing with perception on par with adjusting gas lamps and then denying it. The relationship exists, whether you recognize it or not.

Even if it weren't in many cases the exact same pundits offering the nearly-identical praise while disappearing their previous plaudits down a memory hole, it would still qualify as gaslighting because collectively, an entire industry of experts has decided to act as if history began the moment they started to type, and that the collective previous claims of the group don't exist any more.

If you watched the movie and didn't see how the situation could possibly apply beyond a husband/wife relationship, then I suppose you watch movies differently than I do. If you instead picked up on popular usage of the term without watching the movie, then I suppose might not understand the actual meaning of the term. But if you're defending terms you clearly don't fully understand yourself, please, leave the terms to defend themselves.