> Yep, it's starting to click. My guess would be that this (or the 180 degree opposite) is the flight path of the imager in the golf photo, basically opposite the perceived perspective of the photo

Yes! Typically SAR images are annotated with the direction of flight, otherwise they are very difficult to interpret (unless there are tress, like here).

You are right that, even if the image is acquired from the "upward" direction, it looks like a regular image taken from "below". But this correspondence is not exact when there are occlusions (typically the vertical walls of buildings). The side of the building that is visible is the one closest to the antenna, not the one closest to your imaginary point of view. Thus it looks as if it was transparent, because it is superimposed with the ground next to it.