"As soon as it's explained to them (as I do at every reasonable opportunity) that in fact this is an issue of women's spaces, sports, vulnerable children and male predators, they suddenly start to care. "
Nope, you're wrong.
Nobody really cares about this issue outside of MN.
The people that you talk to nod along and agree with you, but in their head they're thinking that you're totally obsessed and quite frankly a bit weird. They agree because it's easier than contradicting you.
Most people see the your claims of protecting the vulnerable the same way that they view Tommy Robinson's claims of protecting young women, as a cover for bigoty.
You want to see the fact that most people don't think this is a big issue, and that there are far many more important issues in this election for women and girls? Go listen to Women's hour from last week. You lot spammed their emails asking the " what is a woman" question and they discussed the situation at some length, yet not one of the politicians from the 3 main parties would say the magic words you wanted, and they basically fudged the question. Even on a nationally aired show dedicated to women's issues, you couldn't get the answers you wanted.
Because nobody really cares.
They do see that, because of this one issue, you have chosen to side with politicians that have supported or support policies that make life far worse for far many more women and girls than are impacted by trans issue. They see this and they realise that you don't really care about women and girls at all.
So they stop listening.
All those tens of thousands of threads here, millions of words, the tens of thousands of hours you have spent in front of a screen.
Nobody really cares, you have wasted your time, you have had no impact.