“would you wear a tux with a blue shirt”
LOTS of guys have done so through the decades. And peach, pink, grey, lilac, light beige, etc. as well. It might not be fashionable now, but it was, about thirty years ago.
“i would say that a white short IS more choshuv, and the goyishe world is the proof. “
In my experience, the goyishe world wears ALL types of colorful shorts – usually in the warmer weather, but I guess a pair of white ones would look pretty choshuv. 🙂