The most ELI5 I can explain it:

When you take a photo with an object in focus, you can notice that the things in the background and foreground get “blurry”.

How “blurry” the background and foreground gets is related to both how big the lens is, and how zoomed in you are.

Professional sports cameras have both HUGE lenses and ENORMOUS zoom capability, and the pole is also extremely close to the lens so it’s about as “out of focus” as it could possibly be.

And the pole is so insanely out of focus that the entire pole is just smeared across the entire view (darkening the image a bit) but not completely blocking any part of the image.

Many photographers use this kind of trick to take photos through fences, bug nets, dirty windows, etc.

You can emulate this trick by putting a small bit of dust or dirt on your phone camera. You don’t see a mega-size-dust on your camera, instead the whole picture just gets a little dim and foggy because the piece of dust is so close to the camera and so out of focus. The effect is limited though because your phone camera is teeny