The LCUs I served on – some launched in the 1950s – had no urinals. When women joined the crews in the 1970s we had a flip sign on the door of the head. There were no problems.
I sometimes wonder about the men who object to women serving on ships. Did they prefer the company of men and dislike women?
I’ve never served but look in post #37 and see if these are the ‘women’ you want to serve with?
/s