Excellent article, David! As a closeted gay middle schooler, my fear of nudity (when showering after gym class) was largely based on my corresponding fear that I might get assaulted in the showers, or someone might steal my clothes while I was showering. This was compounded by the reality that, in addition to being gay, I'm also on the autism spectrum.
I can see now that my fears were mostly irrational. But try telling that to an 11-year-old boy with (undiagnosed) Asperger Syndrome.
As an adult, my perspective on nudity is a lot healthier. Obviously, I'm most comfortable with it when it comes to sexual intimacy. In situations with platonic/communal nudity, I make sure to be respectful of the other men around me -- however, it's often a great opportunity for casual bonding. I think it's precisely BECAUSE we're so vulnerable when we're literally naked that it can often be turned into an experience of empowering brotherhood.
At the same time, we're self-conscious about body fat, acne, stretch marks, etc. when around one another...so the more comfort one can exhibit toward/around his naked bros, the less pronounced those superficial insecurities will become.