Sorry for the delay in response. The TV is MUCH worse. Walls painted or not have absorption properties, glass is simply 100% reflective. The two have nothing in common when it comes to the reproduction of sound.....while I agree that sound treatments on walls are also a benefit large glass surfaces like picture windows and TV create havoc with your sound....
Seems like you never got a direct answer to your question about the TV placement. Maggies are a dipole planar speaker. This means they put out sound both forward in a 180 degree pattern and to the rear in that same 180 degree pattern.
The large glass surface of the TV creates issues with the rear sound bouncing, deflecting and moving around the room potentially defeating the beauty of what the Maggies do best.
Try this. Place a blanket over the TV when listening to audio only. If there is a difference to your ear, then keep the blanket handy for audio sessions, remove when watching the TV.
