I believe that Hollywood regularly takes liberties with the truth of history, to further their goal of pushing mankind ever downward in morality.
I wish I could say that, but lots of Catholic royalty acted like complete pigs and gave the Masons ammo to use against them.
Showing some cleavage doesn't even begin to cover it. And you're hearing this from a royalist. I believe in the monarchy as the best political system but I have no delusions about royalty being perfect saints. The court of Louis XIV "The Sun King" was a disgusting bordello almost on a par with that of Henry VIII, except he didn't divorce his wife.
I believe the bare shoulders and decolletage look began with the German wife of the mad French king Charles VI, Isabeau de Baviere ( who had an atrocious reputation ). Don't quote me on that, but it had something to do with her, she either popularized it or began it. It was considered scandalous by the clergy. Lots of pictures of her show her with one breast hanging out, but here is a more chaste one.
But a couple centuries later, it was no big deal. Maria Theresa of Austria was considered very pious by almost all historians yet look at how she dressed --
Even when she was older it was the same --
I think trads have a really inflated vision of history and how most Catholics really were. All of Europe was officially Catholic at one time but it's not like everyone's whole world revolved around the faith. I would guess almost all were baptized by water but many didn't care much about God in their hearts, and that is why saints used to preach about the fewness of the elect. But wearing some vain or revealing clothing is not the worst thing people did.