Isn’t this just a simple case of “get the moisture away”? Blowing into the dishwasher doesn’t move the moist air away, it just moves it around in the box. Blowing out pulls the moist air away from the dishes and out into the room.

If your box fan was pushing dry hot air (like a hair dryer), hot enough to meaningfully speed up evaporation, then blowing in would probably be better.

Why does anyone believe anyone is on the fence right now?

There are people who had made up their minds months ago, or longer, and cowards.