@Baileyonice , as far as I can tell, your argument is:
I) Biological sex results in 'typical' male and female behaviours
(You haven't told us what these typical behaviours are, but I believe big boobs and handbags were mentioned)
ii) We can all browse through a list of these typical behaviours, total how many 'male' and 'female' typical behaviours we have, and therefore determine whether our gender identity is 'male', 'female' or 'non-binary'
(presumably if our split is exactly 50-50 we're non-binary. What percentage of male or female typical behaviours is required for being male or female is so far undetermined. Perhaps this is a matter of personal judgement)
The question is: once we have determined our gender identity, what are we supposed to do with it?
Here's an analogy:
I) Biological age results in typical 'elderly person' and 'young person' behaviours
(E.g., elderly people may be more likely to enjoy garden centres and sudokus than nightclubbing)
ii) We could look at a list of typical age-related behaviours and determine whether our chrono identity is 'elderly' or 'young'. For example, if I prefer garden centres and sudokus to nightclubbing, I can determine that my chrono identity is 'elderly person'
Now I've determined my chrono identity, what am I supposed to do with it?
Should I dye my hair grey and adopt a stooping, shuffling walk?
Should I have surgery in order to socially pass as elderly?
Can I enter veteran races and sporting categories on the basis of my chrono identity?
Can I demand to be accepted into retirement homes, and demand a pension, a bus pass and a free TV licence?
Or would we say that dying my hair and adopting a stooping, shuffling walk are insulting biological appropriation? That having surgery to pass as elderly would be attempted deception, a cause for concern about my mental state, or both? That I can't enter veteran races and sporting categories because I have an unfair biological advantage? And that retirement homes, pensions, bus passes and free TV licences are given to people of biological old age due to their biological need and not due to their propensity to enjoy garden centres and sudokus?
Why is gender identity any different to chrono identity, and why should anyone take gender identity seriously?