While that is true, the main reason to dunk on the person isn't that they looked into this empirically, it is having the balls to say that you were surprised by the results and treating this as something new. The analogue is that we wouldn't make fun of physicists studying gravity and say "everyone already knows gravity is a thing!", but if they then wrote a NYT article saying "I was surprised, maybe there might be a thing like gravity. Until this study I didn't know about gravity, I just assumed Aristotle was right and heavy things fall because they contain more Earth element and want to be closer to the other earth." and then go back to using Aristotelian mechanics.