I agree with this with the further point that you kind of have to lean into the fuzziness. In D&D, the wizard may be an Arcana savant, but have no idea of the name of the current king, because he doesn’t care. Even without History proficiency, he still has a +4 to History rolls.
Conversely, the dumb merc with -1 Int and 10 years experience is still going to know a hell of a lot about making battle plans to win fights, or else he would be dead.
And who knows, he might end up Master of Coin one day.