However one chooses to see it, the WBW thing is a separatist thing. Humans do this kind of thing to keep out people they don't want, to make them feel superior to others, to express their dislike for others or sometimes just to keep the party limited to people like them.
Like many separatist actions, this particular action was intended to be divisive. I personally know one T girl who went to Michfest and who passes very well. She passed there, completely. But she told us of several events where T girls who didn't pass were treated with aggressive hostility, initiated and carried out by WBW. The WBW attitude fueled the fire making it almost dangerous for T girls who weren't totally passable. It helped develop a gang-like mentality. This happened about 4-5 years ago. I don't know if that hostile attitude still exists today, but I do know, when it did, the WBW mentality was the primary catalyst.