Why would you need to segregate based on sexuality? If it's a sexual attraction thing then ask yourself whether you are attracted to every single person of the gender that floats your boat? And if you are then do you take action about every one of them? If the answer to the last question is anything but no then a) I have no idea how you found the time and b) I didn't realise they allowed unrestricted access to the internet in prison but good to know that these forums really do have a wide spread of contributors.
At the distinct risk of stating the obvious - it's almost inconceivably rare for people to show no discrimination at all in who they are attracted to and that applies whether they are heterosexual, homosexual or neither. There is absolutely no reason to assume that you are any more attractive to someone of the same sex than to someone of the opposite sex or that just by being in your presence that they will be unable to resist your sheer unbridled magnetism and that this person will throw themselves at you despite all attempts to discourage them. If on the other hand you are constantly bothered by unwanted attention from both sexes then you have my condolences and feel free to ignore the above.
In relation to the original post - I did actually read the article and it seems like an issue of inadequate training there since the manager confirmed that in store a transgender individual should be able to use whichever changing room makes them feel comfortable. As a general principle it seems both fair and reasonable that transgender individuals use the changing rooms for the gender they identify with - the number who will then abuse that is likely to be vanishingly small and they can be dealt with as appropriate but there's no need to take what is a difficult subject and something which causes considerable emotion trauma for people and assume that all will cause problems. It's also worth pointing out that they could well have body issues as part of their transition so there's a fair chance they'd choose a cubicle if it's offered which entirely negates the issue.
apologies, my post was meant as a bit tongue in cheek. but to reply to some of your question/statements,
Why would you need to segregate based on sexuality?
surely we already do....male and female separate changing rooms, not purely down to sexuality but it certainly is a factor.
At the distinct risk of stating the obvious - it's almost inconceivably rare for people to show no discrimination at all in who they are attracted to and that applies whether they are heterosexual, homosexual or neither.
of course not, I'm not attracted to every woman I see and I don't expect every woman that looks at me is attracted to me (though they'd be a fool not to be

)
There is absolutely no reason to assume that you are any more attractive to someone of the same sex than to someone of the opposite sex or that just by being in your presence that they will be unable to resist your sheer unbridled magnetism and that this person will throw themselves at you despite all attempts to discourage them.
not sure where my post gave the impression that I thought a homosexual man/woman in same sex changing rooms were going to start throwing themselves at any and all nekkid body they see?
let me ask a question, genuine this time......
if someone is, i'll use the word
generally attracted to the same sex as the room they are changing in, is it ok for them to be there?
if you answer yes, then I assume you have no issues with a male changing in a ladies changing room as long as there is no one in there they are specifically attracted to, converse is true for women in a mens changing room???
if the answer is no, then your post for the most part is irrelevant