"Views differ on the meaning of sex...."
Views differ on the creation of the universe, but the fact is it happened around 13.8 billion years ago, and not on 22 October 4004 BC at six in the evening.
Spot on, Millytant. And it doesn't really matter most of the time what people believe "on their own time" - if your conceptual framework helps you to make sense of a chaotic universe and live your day-to-day life, crack on. I may not share it, but I respect your right to hold to it.
Where it does matter is if the rest of us are coerced into it or somehow forced to abide by its implications - for instance by having creationism taught to our children in school, or when a company in the US makes use of its (Gorsutch-sanctioned) right to refuse to provide its employees with birth control on the company healthcare scheme because the CE is Catholic.
And that ultimately is the problem with transgenderism - it all comes down to the practical consequences. Do we force women to share prisons with male-bodied sex offenders? Do we remove women's rights to ask for a female HCP, or get changed in open plan changing rooms that are free of penises? Or compete in sports with other female athletes rather than being placed at a massive systematic disadvantage?