The answer to this is simple. There is a broad distinction between proper artistic representation of the human body (figurative art) and other “art forms” designed to arouse.
It is not true that the only models available to Renaissance artists were male. Male models were more common, however female nude models were also not uncommon at this time.
The link below is an article on this particular topic in relation to the artist Michelangelo:
renresearch.wordpress.com/2011/02/11/men-with-breasts-or-why-are-michelangelos-women-so-muscular-part-1/
Nude models are common today among many artists, this includes catholic sculptors and painters. The Church, throughout the centuries has commissioned works that involve nude models. It continues to do so today and there is nothing wrong with this.
An experienced & competent artist should be capable of treating a model with an element of professional detachment and respect.