I've no issue with both sexes using a proper individual room, ie a loo, a sink and a hand dryer, with a lock on the door.
I have massive issues sharing a large room with individual toilet cubicles with males.
I know exactly how I would feel, if I was inside a cubicle and a group of people with male sounding voices came in. Who, out of us, would leave the cubicle whilst a group of unknown people who sound like they have male voices stood outside? In a space that's closed off to the rest of the pub, restaurant, store, whatever? Yes, I'd maybe be doing a perfectly lovely group of people a complete disservice, but how the hell can I tell if they're friend or foe??? I'd have no idea how many of them there were. I've no idea what size they are. All I have are the voices. And those voices, even if they had no idea I was there, would be telling me to stay still, stay quiet and stay unnoticed until it was safe to leave.
I'd either have to wait until they all left, or text my husband and ask him to come in to the "gender neutral" toilets and be there when I opened the door.
What a fucking way to live...