This is very much a question of Catholic art in general, as it appears, in very deed, on the walls and ceilings of many very old churches.
More than just shirtless men, the fact that the men sometimes have nothing on at all is a question of even bigger importance, because today indeed the minds of men are so polluted that we really must wonder whether we should allow such things to be displayed as is (and not perhaps creatively covered, even if only until a purer age, if we may hope for one to someday arrive), or whether it is purely a matter of the minds, and therefore not of the arts.
That the human body is something good and beautiful (unless distorted by either the death of age or the gross intemperance of the glutton) is a fact which no Catholic can or should deny. That the lack of clothing can and does incite human beings to have sinful thoughts, is another fact which no Catholic can or should deny. It is, after all, one of the reasons why we wear clothes. And if the human beings in the real world must wear them, I can't imagine why people ever came to decide that people in paintings, painted more or less "photo-realistically," ought for some reason to be excused from wearing them.
That the Church should have allowed such statues or paintings in it's own buildings, REALLY remains a mystery to me. I think that if it makes sense for human beings to wear clothes, it certainly should hold true that we shouldn't see them in any case (outside of the profession of physician) without them. But perhaps there is something I, being a product of this puritan culture, may be overlooking.
I dare say that shirtless men have had far less effect upon ladies than the other way around typically does. If it's a matter of a man without a shirt, I think you'd have to go pretty far to argue the young ladies will be in danger... except perhaps when the young ladies have given themselves to reading the same kinds of dirty stories and looking at the same kinds of dirty pictures that men once ogled of women. By that standard, all of us should at all times remain locked in their houses, as mutes and blindfolded, because today, literally ANYTHING can be made into something filthy, by the minds thoroughly corrupted by modern media and modern *ahem* "arts" ... >tries to retain her breakfast<. But if you're talking about something that as a matter of course leads even normal, ordinary people into sin... now red flags should go up. And that's why this question I think is very bewildering to a LOT of people.
People without clothes is an occasion of sin. Why don't we think it's true when those people are mere paint? I have NO idea...