I don’t think it’s fair to blame buyers for this, at all.
But this serves as an example of why local architects - in addition to reasons of practicality and useable floor space - reject curves in their residential buildings. What is originally drawn as a smooth, svelte line in plan will almost inevitably be value engineered into a faceted series of abrupt lines forming a “curve”.
Office projects permit a budget for nice curves (see HPA projects) but a res. project is far less forgiving.