I still stand corrected, there are other constraints limiting the height, not just viewcones. You suggest that viewcones are the only thing limiting the height of the building.
Even without viewcones, how much higher do you think this tower could go? This site is highly constrained so you can't increase the floor plates to make up for lost space due to additional elevators needed for taller towers. Like I said, the city even expressed interest that this tower be taller. The developer isn't going to do so it that reduces leasable space. Developers know what they're doing and fortunately or not they don't cater to unrealistic desires.