> No one cares at amateur level

Except people clearly fucking do for some reason, and all that's going to happen is make life worse for women both cis and trans. Trans women will get excluded, and cis women who are "too good" or not fitting societal ideals of femininity will be accused of being trans. This is already happening to children.

> If you chose to identify as another sex

When did you choose to identify as the gender you were born with?