> Is it 'subjective' that many activities are segregated by gender in the West?
You're conflating sex and gender. If you used the two terms as others do there's no surprise.
Washrooms, in almost the entire world, are sex segregated. They aren't gender-segregated in the sense of transgender because they forbid all males and allow all females, or vice versa.
> If a person doesn't like that, how is it not a logical response to try to change their gender?
The washroom isn't actually gender segregated, it's sex segregated and you can't change sex. The words you're using are chosen to subtly obscure the situation.
> So you're telling me that a boy who identifies as a boy is fine to change with the girls at PE and do their activities? OR is there 'baggage' to being a boy in this scenario?
It sure feels like there's baggage to being a girl - being an object for you to shower next to, not a person with their own privacy rights.