Romanesque art is generally a powerful transition: from the classic period on one hand, and Byzantine splendor on the other to something uniquely Western: rustic, individualized, and direct. It came naturally to the West to bare Our Lady's breast; it is the same unsophisticated feeling that St. Luke carried over to us in the simple act of veneration of the woman in the crowd: "Blessed is the womb that bore You, and blessed are the paps that gave You suck!"
When we look at these discolored, vandalized frescoes, we understand something about the Western culture, raw and simple, and unafraid of its humble origin. The perfection of Renaissance somehow masks that aspect of our psyche.
This is how these "dooms" might have looked like, before the so-called reformers' whitewash got to them:
We also forget that medieval art was not perceived as “reporting,” but was highly symbolic. Figures weren’t just themselves but represented something else. Furthermore, the spectators knew what they represented; that is, they could read these symbols.
For example, early Nativity scenes (post St Francis, at least) always had a certain set of figures, among which were the Ox and the Ass. Naturally, anybody looking at it knew that the Ox and the Ass represented the Gentiles and the Jews, just as the Three Kings represented the “three races of man,” and were shown as being of different ages because they represented the “ages of man.” So visual works and even folk representations were laden with doctrinal content.
This, of course, is one of the reasons that visual representations were a major target of the so-called reformers.
My wife and I got a good look at Romanesque sculpture in France this past winter. It satisfies spiritually in a way the more literal gothic style fails to achieve.
ISTM that our discomfort at seeing nudity in a sacred context says more about our own disordered sinfulness than anything else.
Cheers and best wishes.