There are a few unisex bathrooms on my campus. I've used them, with both females and males present, nothing has ever been an issue. Someone who identified as a man has used the women's bathroom as well, no one cared, but he apologized anyway. In my state, WA, we have made it mandatory to make all single stall bathrooms gender neutral as well, any business that doesn't comply is fined. This whole superstitious culture around bathrooms is ridiculous.