Bright colors are not about being visible. It is about being feminine. Dark colors, white shirts, gray and black are for men. Women wearing them appear masculine and, for many men, less attractive - they claim man's territory.
I don't think fashion rules are as strict as you are making them out to be. For one, there's the 'Little Black Dress' phenomenon, and I don't think many men would find them unattractive or masculine. Cut and style trump color, and there are lots of white and grey dresses that look stunning.
Same for skirts. It is not about the length or twirling or what is visible underneath. Women in pants look masculine, and many men don't like it. It is man's duty to be masculine.
The colors' effect can be appreciated when other things are kept equal.
Imagine a man, dressed in black and white, standing near Hepburn. Wouldn't they look better, especially in a photo or video, if her dress were not black?
I often notice that gentleman's and lady's figures show up as one whole piece during dancing or dance video, because both are black and indistinguishable. To avoid this, who shall wear a brighter color?
before I return us back to the topic...who gets asked to dance (for those of you who may have forgotten)...let me just say that this is why dh needs to appreciate me...I have only been in WHBM once...loved the stuff, consider it too expensive...game over..unless I have a major life event, if I can't buy it at kohl's it won't be happening...