Post Rock BEFORE Simon Reynolds

Not really. Art Rock (Talking Heads, Bowie, XTC, etc) was more about being progressive-while-playing-pop-music and relied heavily on the visual aspect, too. Post-Rock had always been less song-oriented, more experimental thing, which is pretty far from popular music. Also it was never about tripping out, so it's NOT a form of Psychedelic/Space Rock, too - something many older Prog fans don't seem to notice. Post-Rock artists do not "jam", there's no blues-influenced soloing and so on. Again, this genre has always been closer to ambient and electronica than to conventional rock/pop music