I had an experience in Ireland....
We had a unisex bathroom... that's right showers, toilets, guys and girls both were in the same room...
However, the showers and the toilets had stalls... Stalls with walls that were both low to the ground and high to the ceiling. So, while in the main room where the sinks and mirrors were, both guys and girls would be going about... No one saw anyone naked or "sitting" or whatever. One entered the stalls fully clothed and one left the stalls fully clothed.
It was rather strange for me to take a shower in the morning and chat with a guy showering in the stall next to me... but honestly, there wasn't anything untoward about it.
My only thing would be... if I were in the facility alone... and a man walked in... How would I know if he were just there to attend to his business or if he were a perv or dangerous?