Hold on let me read it again for ya -
This water vapor that partly steams the food, resulting in moisture saturated air that in turn prevents more moisture from escaping
Dude.
The first sentence:
it moves way more air than a normal oven, thus removing water vapor faster.
Says that the sentence you quoted applies less with an air fryer than a conventional oven.
This water vapor that partly steams the food [is removed more slowly in a conventional oven], resulting in moisture saturated air that in turn prevents more moisture from escaping