"The emperor Caracalla was cruel, but he built beautiful things."Emperor Caracalla didn't build anything, and even if he did, he couldn't have built something so massive on his own. More likely than not, masses of slaves build this "beautiful thing" at the direction of artisans who designed it. Certainly, slaves worked this "beautiful thing" out of the sight and, therefore, out of the minds of those who enjoyed it.
The decadence of opulence should not be admired but condemned.