You do realize that in order for the top block to move downwards "as a whole", there has to be column failure on all four sides of the building. This did not happen simultaneously, as was also the case in WTC2. The tilt occurred from the very fact that the South Face failed first, and that tilt caused the antenna mast to tilt. The North Face on the opposite side was the last to undergo collapse, first on the 94th and 95th floors at the impact site and then near the northwest corner to the right of the impact hole. Only then did the upper block fall vertically "as a whole". That the antenna should undergo movement prior to anything on the North Face is *expected*, as it was the North Face that was the hinge for what would become the upper block.
It was also the absolutely worst perspective to see the lean.