I hope the clear glass at the top is for a more effective solar chimney but that's probably too optimistic.
The rounded corners are the only thing that keeps Brookfield somewhat interesting. Otherwise it's just a glass box
Some peoples' obession with minimalism is likely just a case of rationalizing the buildings they already have. Buildings exteriors have a few more performance objectives than an iphone case, and there's only so much "refinement" possible on the same basic design.