Also, if public bathrooms were fully enclosed locking stalls, would you feel comfy it being unisex? In my head, the only thing being shared in that case, are the sinks.
(I don't want to hear the argument about transgenders using whatever bathroom. You can never tell if the same gendered person in the stall beside you is homosexual or not. From my research, sexual preference and biological differences don't play a huge role in predatory behavior.)
更新1:
When it comes to waiting for an empty stall, there are locks with an "occupied/unoccupied" sign switch on them. If that were also in use, what would you think?