Uhh...it is a TV, 3x3 isn't really that bad. Also the icons are larger and specifically designed for ATV. The main screen is 5x4 I believe...3x3 huh? I see we're still focused on wasting as much screen real estate as possible. I'm sure the icons will look great on a 70" HDTV...
I do agree with you on iPad/iPad Pro where the rest of the screen could actually be useful, but this is a TV.