Just asked my ten year old if they would like to share a toilet with someone of the opposite sex the response was no yuck
Presumably there are no males in your household?
It feels as though many posters have an entirely erroneous picture of what mixed sex toilet facilities are like.
We are NOT talking a single room with cubicles and shared wash basins, as is the case with single sex ones. Each of these toilets is entirely enclosed, (just like the toilet in your own home is), and usually has its own hand washing facilities.
Such a provision is infinitely better than the single sex cubicle option. Privacy for all, and no longer a room dominated by those who choose to use it as a social/smoking area to avoid having to go outside at breaks.
Why people are seizing on the trans element of this, rather than how much better it is for EVERYONE, I don't know.