I find some of the views on this thread really hard to get my head around. I have no issue sharing toilets or (cublicled) changing rooms with transwomen, none at all. Yes there is a risk that some perverts might try to take advantage of that, but that is not the fault of transwomen and I believe we should all work together...
Genuinely, the majority of posters here agree that the problem is not transwomen. The problem is men. All men, transwomen included.
Mixed sex facilities have been shown by many studies across the world to increase the likelihood of sexual assault by men upon women.
There are ways to provide UNI sex facilities that would cater for all and not increase the risk of violence to women but those are more expensive, especially if being modified from existing facilities.
That and many workplaces, public spaces don't seem to be aware of the laws around such spaces.
And many simply make female facilities mixed gender because that's the easiest way round the perceived issue. Leaving male facilities single sex.
So, lots of problems, not just a preference. And this is being repeated in all aspects of life. Medical care, , prisons, workplace, sports etc etc
Female provision is being made, effectively, free to all whilst male provision remains single sex, protected.
THAT is why so many here object to any and every male who encroaches upon female spaces. Many of us could and did type posts very similar to yours and have since hardened their stance due to an issue that made them re-evaluate their position. I did much the same a few years ago and was taken to task by a long gone poster who gave me some more information and a quick shove into less "be kind" waters.
I've been learning more and changing my mind, developing my own perspective, ever since.