It would be like me saying ‘yes I believe in fish and monkeys, and I believe that we can have monkeys with gills.’
Don't think that works as an analogy - fish and monkeys are not 2 categories of one species. A fish can't be a monkey. But a human can be male or female. Or intersex in some cases. (ie where sex isn't clear, not '3rd sex').
it’s no longer legally necessary and it was never scientifically correct. The GRA was always a legal fudge.
It's still necessary because people are entitled to get married as their acquired sex. There will also be times people need a corrected birth certificate to protect their privacy.
Anyway I’ll ask again, and I’m sure I’ll be ignored again do you believe that humans can literally change sex?
I'll answer you again if you like? No - not in terms of chromosomes. But yes in terms of hormones, some biochemical aspects, some physiological aspects, legal status and sometimes in day to day perception.