Its about conflict resolution when we as a social animal always inspect the humans around us in any environment.
First impressions are usually correct or not are fixed within seconds.
So
You are ok with some castrated males in your changing room.
¤ Provided that the castration was done with the sole purpose of gaining entry into the changing room.
You do not want some females who have undergone a double mastectomy in your changing rooms
¤ Once the mastectomy was done with sole purpose of gaining entry into the Mens changing room.
The current expected social behaviour is :
:: if you are a man you stay out and
:: if you choose to look like a man you stay out. This is due to the risk created by men entering spaces which should be Women only.
And yes the result is
▪︎ that women who choose to alter their bodies are then depending on men to make a space that included them. Or go about organising a new space for themselves.
▪︎ that women reject men from womens spaces so men need to solve male violence in male spaces. Or go about organiaing a new space for themselves.
That ^^ is self policing the space by the individual who knows their own sex and who choose to follow the social rule.
You are claiming that you are unable to look at an adult human and sex that person to a degree of accuracy.
[Others will say 'what about Lesbians' because any women dressing more mascline must be a Butch Lesbian.
And as above females who opt out by action.]
Anyway...
You want to add an exception to the rule and allow some men in.
But you cant sex so set a third rule.
That is a target beauty standard based on what an ideal woman looks like and an allowable degree of differentation.
So you will not object to some of the castrated males who seek entry once they reach your beauty target.
You will want to exclude some castrated males who seek entry but fail to reach the target you have set.
Your selection rule is
□ meet target and be female and not have 'that' double mastectomy reason
□ meet the target and be male and be castrated to be allowed in
This rule is not a social standard.
But your rule creates a point of conflict
You gard the door by being in the space.
And you agree that you have a righ of access as you pass your own criteria.
K is male, castrated, but fails your beauty test.
If he had passed you would change beside him.
You need a way to enforce your rule
so you request K leave and K will not
so you request via management (a gard with an appeal process who agree he is a man) and K will not leave
so you request via management via the legal authority (the police with full legal powers) who can forceably remove K.
You gard with no need for you to look in anyones underwear.
And K has an obligation to prove K meets the female ( not being castrated nor being passing enough for a beauty test ) provision in law if and where that exists.
Most men will chose not to break the social expectation so your rule will not be needed. Most women will pass on the beauty standard alone so you wont object to them.
Most other women can sex to a very very near 100% degree of accuracy so management will eject K without a problem and allow most females in with no problem. So chances of you to ever need State involvement will be low.
When self regulation fails society reacts to adjust to the new normal or by enacting clear legislation to prevent and punish poor choices.
Eg
Outraging public decency
The separate offence of outraging public decency is when someone does something lewd, obscene or disgusting in the presence of at least two members of the public.
https://www.police.uk/ro/report/rsa/alpha-v1/advice/rape-sexual-assault-and-other-sexual-offences/indecent-exposure-flashing-offending-public-decency/
^^ catch all law that is subjective to what is the social norm.
So at the moment self regulation is failing society and to such an extent that it is outraging the public and they are actively debating what is or is not decency.
In the case of the employer choosing to adding a contract term that a female employee must change in a room with male U at all and with male U but not male V.
So its like you call the police and they pushed you into the room with K and insisted you cant come out until you change beside of K.