I have an invisible disability which does sometimes necessitate the use of a disabled toilet. I would be incredibly pissed off if staff looked at me and said it was only for people with “actual” disabilities. I do wonder if the staff said this unprompted or if the individual involved announced to them that she was non binary and that’s why she needed to use the special loo.
However, disabled toilets are not equivalent to “gender neutral” toilets and shouldn’t be treated as a space to accommodate non-disabled people who have special identities.
the rights of disabled people rightly trump religious rights when it comes to transport (service dogs are allowed even if a religious driver objects). In this situation the rights of disabled people should similarly come first.