Although the OP didn't mean the title question as a real question, rather as an answer to a different question posted on the forum, some seem to have mentioned that a naturalist shouldn't be embarrassed of our G-d created natural being. A real answer to the question is hopefully self evident and completely unnecessary, that fact being the point of the thread in of itself, which some seem to have missed. Nevertheless, I'll post a quick synopsis of my understanding and what I've learnt.
We were created perfect and pure, in the image of G-d. Adam and Chava walked around Gan Eden in perfect purity and innocence, without any of the sensual and crude thoughts and desires humans have today.
However, that changed after the Etz Hada'as. A yetzer hara was internalized in them, and they started looking at nakedness with the kind of crudity that we are used to associating nakedness with. They them realized that their essence had diametrically changed, and they were no longer perfect. The covering they put on themselves was an attempt to cover that imperfection.
Today, the world has gotten to such a sick state that we glorify the imperfection that the human body symbolizes. Therefore, people try to show off their bodies and imperfection, for the flaws of nakedness are their pride, rather than trying to fix it.
Us Jews perform a circumcision on our newborn infants, setting the tone for life that we are not here to glorify and magnify the shortcomings of this world, bit rather to glorify and magnify the presence of Hashem in it by subduing and overcoming these shortcomings for His sake. That is why modesty is such an integral part of our religion.