Local laws change a lot.
In Australia if you present as female use the female toilet, If male use the male toilet. If you are in Drag use the toilet of your sex. Confusing, yep.
But most large entertainment places in Australia also have M/F toilets or F/M, which means Unisex. They were supposed to help out in the female rush for the loo in theatres etc. But they have also become synonymous with if you need a loo use it.
I think, and this is without personal experience, you are more likely to get reported to security for loitering in the toilet rather than for using one of the 'wrong sex'.
I also read that some places in the USA seem to have more problems than needed with people who need to use a toilet.
I use to do lots of bush camping in Aus and we basically had the boys bush and the girls bush. If it was organised someone would dig a hole and place a deck chair without seating in the girls area.
Somehow the need to empty bladder, bowels or anything else never caused any great excitement.
To be honest I still do not know why it does, unless you have a baby and have to check its motions, something I leave to its parents.