Post hoc ergo propter hoc?
The real question is why wasn’t he shown as the original Jewish David, circumcised?
To downplay that, the Protestant Reformation eliminated the crucifix, reduced it to an abstraction, or omitted or partly obscured the nudity of the crucified Christ. More broadly, Protestants were hostile toward even Christian art in churches. Taken to its logical conclusion, this resulted in a comprehensive preference for plainness in church architecture, in services and prayer, and in personal manners. Something of the same thing happened in Islam, with the conquering desert tribes destroying or painting over Christian art and rejecting any depiction of the human form.