Did the apple really fall on Newton's head? What kind of apple was it?
It doesn't matter. These questions are inconsequential to the higher level phenomenon being communicated. The story of the apple plunking Newton serves to illustrate the idea of gravity, an enigmatic concept which makes things fall.. attract.. pull.. push.. or something. This nebulous theory leaves questions unanswered, even today.
We often try too hard, getting into the weeds of allegories, lost in inconsequential detail. This magnified perspective leaves higher level metaphors beyond our vision.