The article specifically did ask two other people, who gave more equivocal answers, saying that the flame is part of the answer but that most of it comes from just the high temperature.

Either way, on this particular question, you can visually see the flame ignite the aerosolized droplets. Note that it's not unique to Chinese or wok cooking, as you can see a similar phenomenon with French chefs sauteing mushrooms in butter, where the flame can flare up at the edge of the pan. The taste comes specifically from that flame above the food, not below the pan.