I have a theory which I will test in this weekend.
It is very simple: the A119 is positioned too far away from the glass (compared say to cylindrical cameras, like blakvue or mini), hence there are a lot more of reflections visible.
The fix involves a wedge (about 20 degrees) which would sandwich between mount and the glass thus bringing the lens closer to screen.
My first stop would be hardware store, specifically looking for black plastic doorstops which I can use as the wedge (I can always sand them down to correct angle).
The distance is worse with GPS mount as it is thicker.
The reflections are quite bad due to car stereo ending up in the centre of the screen in full colorful glory (even if it is dimmed). The interim solution is to turn off the stereo screen/lights. While I can deal with stereo, I cannot deal with clock/fuel consumption display, as even at the dimmest settings (which I do not like as it dimmer is for everything, including the instrument cluster) is very visible in about 1/3 from top of the screen.