So, I truly want to understand before I get attacked. We’re here to learn right?

I’ve recently been watching a reality show where a person who was previously identifying as a female adult woman go through affirmation surgery to transition to be “male” with appendages and all but wants their pronouns to be they and them.

Please correct me if I’m wrong, when one transitions, is it typically to go from one to the other? If that’s not the case, then okay got it lol. But if it’s the case then what is the main purpose of completing transition to appear like an adult female? I thought it was to operate within the binary basically but just moving from one to the other?

If one is non binary wouldn’t it make sense to stay where you’re at physically and make changes by language? Idk if I’m phrasing this correctly I’m just confused lol

I’m genuinely wondering.

Edit: I really appreciate everyone taking the time to explain to the best of their abilities! Im gonna try to sit with some of the things I read and process!