I beleive that the external ugliness in the world in art and architecture is just an outward manifestation of the state of the souls of most of humanity right now.
It is more than that though, because the changes in architecture didn't come from the tastes of the ordinary people, but from the bad intentions of a small group of people who dominated art and controlled the Church's acquisition of art.
So it's usually expression of the gnostic mentality of the freemasons.