You do realize that the vehicle was coming "towards him" only in the sense of its ground track, right? I.e. it was on a path to fly over him, not into him. As such it would have been able to move upwards out of the frame.
As he said, if it was getting closer it would get bigger. Yet the vehicle remains the same relative size and clarity.
This is because at long distances an object's apparent (angular) size doesn't change much as it gets closer. Also because the conditions for contrail formation are changing as it gets closer. Its contrail is getting shorter which offsets the fact that it's getting closer.
Not at a distance like this...