Other countries have solved this issue. 2 or more small rooms off a hallway, each with a toilet, often a sink, and a full-length, solid lockable door. If there’s a line, both men and women are waiting in it.
My grocery store did this a while back. Fellow customers were more helpful than the staff, who didn’t know where things were from one day to the next….because they’d been moved while they were off shift. You’d meet another shopper: “Have you seen the milk?” “Yes, it’s over there. Have YOU seen the bread?”
Jeri wouldn’t care.