To drag the humanity in a different direction.
Notre Dame and other great architecture is inspired by great archetypes, it's a well crafted expression of those archetypes to the extent it's possible in stone and concrete. Simply looking at it drags us closer to the ideas behind it.
But not everyone agrees with that direction. There is a large number of people who would rather take humanity in a different direction, and they build this oppressive architecture of bland geometric forms.