Callistemon21
It is ridiculous and worrying because someone could answer that they may have been assigned female at birth but they now identify as male so wish to turn down the appointment.
That could cause problems for them in the future if they refuse to attend.
I do understand what you are trying to say with this, and it's a relevant sentiment, but i think it more likely that trans men would respond better to the term 'assigned female at birth' than to the term 'women'. Reverting to referencing the term women, alone, surely puts this trans men at greater risk than the term being currently used?
There is often an air about these things of 'well, in that case it'll be their fault for choosing to live that way'. Much the same attitude was had about gay people and hiv back in the day.
What does it matter to you what a stock letter uses for salutation, OP? Don't you have better things to do with your life?
I've actually never met a trans person who denied that sex is real. The issue is with gender. You are assigned a gender at birth based on what is known or observed about your sex. This is where the language about 'assigned whatever at birth' is talking about.
However, if we want to talk solely about sex and the facts of sex? Did you know that actually not everyone has xx or xy chromosomes? No really, look it up. This has been proven. And 1-2% of our several billion global population is intersex. That's about 400k people in the UK.
Just food for thought.