On iOS 14 I have set the camera's access to Location Services as 'never'. If I inspect the EXIF on iPhone photos that I've moved to my PC the GPS fields are blank.
Facebook can solve a location from the content of the image. Listen to yourself. Even you can identify a geographic location from many images, easily.
I don't know, it's kind of a stupid idea, give Facebook an image and yet the expectation is, they're not supposed to know or understand anything about it?
Which I wish they did...