The Russian Orthodox Church where my wife and I sometimes go (neither of us is Russian, but she’s an Orthodox, and that’s the only church around us) discourages wearing jeans to church.
Listen. I'll all for informal discouragement of lots of things...including some wardrobe choices.
Big difference 'tween informal discouragement and outright legalistic bans announced. Once you start naming wardrobe choices in official bans, there's nowhere to easily draw a line. And then it gets constantly updated according to the O.W.P.C. (Official Wardrobe Police Committee)
C'mon. These are religious adults.