According to Nietzschean philosophy of art, beauty in art was invented to appease a saddened soul or a troubled society. Ugliness in art, on the other hand, was invented for stable societies that seek a sense of threat and excitement when these are difficult to find in real life. That is why he refused to follow Schopenhauer in his interpretation of the Greek tragedy, that tragedy expresses the yearning to renounce life. Nietzsche, on the contrary, saw it as proof of the strength of the Greek soul, which allowed itself to contemplate the tragic without being conquered by the feeling of existential despair.
The ugly and the sad once again appeared in the art and science of Nietzsche's time: for example, in the naturalism of Zolla's novels. His appraisal of these movements was less positive than for Greek tragedy. But in his view this movement proved not only the vulgarity of the 19th century, but also its strong spirit, which allowed for a greater degree of honesty about human nature, about its fundamental bestiality, than past centuries did.
With advances in science, one lives with much less fear of death and of the unknown today than in the 19th century. And because of social advances, for example in labor rights, one lives today with more comfort and dignity than the middle and working classes of the past did. So I would say, based on all this, that the psychological need for beauty in art is lower than ever in our days. What has really increased is boredom. And boredom makes us long for challenge, threats, terror, in short, the ugly.
Another thing, too: secularization is not very conducive to beauty in art. The beauty and loftiness of the ancient Greek temples, the Gothic churches, the Egyptian pyramids were not merely the result of the architect's talent and inspiration. These qualities were produced with the very conscious intention to provoke in the worshiper awe and respect for the divine. It is as if the noble appearance of these buildings invited the faithful to leave his vulgar, sinful nature outside and behave in a more civilized, virtuous, divine way on the inside.
In this de-divinized world, who would aim for this effect? Who would need it? Banks? hotels? Any secular institution that sought to project itself in this way would be the target of ridicule, and rightly so.
The same applies to democratization. The great architectural projects that we so admire today, such as the Pantheon and the Taj Mahal, were built by people we would today call tyrants when they wanted to project their glory and wealth in order to provoke in the commoner the same feeling of happy submission to the superior which was described above. That is also why the royalty and aristocracy of Europe were so garishly dressed until the 20th century. The countless jewels, the expensive and shiny fabrics, the loose-fitting clothes: everything was meant to overwhelm the commoner and inspire submission by reminding him, by visual contrast, of the insurmountable superiority of the sovereign over the commoner. Imagine if a president of a democracy dared to dress like Louis XIV today? Again, he would be mocked, and rightly so, even if he had the money to dress himself up with so much pageantry.
In a democracy, we do not accept the superiority of the president over the voter. And this is reflected in fashion. The president does not stand out very much from a crowed of well-dressed middle-class citizens - so doing is no longer allowed, nor is it necessary.