Thank you for the word salad proving you have no idea what you're talking about. Do you even know what focal length is? And van? Did you bother to look at the gif provided? there is no van.
My bad, I meant "truck" instead of "van". I'm sorry that it made you so confused. But getting back on topic, you can't transfer the focal length between to approximated objects, like the truck and the barn, to objects in space, where such objects are thousands of miles apart from each other, and the fact that there's infinite focus in space.
For example, the Moon is smaller than Jupiter. But, if the Moon's transit where to happen in front of Jupiter, the Moon would leave Jupiter completely covered. Same thing happens between the Moon and the Earth. So, the Moon, would never look smaller than the Earth, as it's shown in that animation.
If you can show me that trick with the focal length, but with actual celestial bodies, then we'll talk.