Because these legislators are not doctors they are not informed
adequately to make the decisions they're about to make for
political reasons. Genetic gender assignment is a very complex
process that does not always result in a gender-decisive result,
but instead, in many cases it results in an individual who is on a
spectrum somewhere between the two sexes. In such cases,
there is no amount of teaching or instruction of any kind that
can or will somehow inspire the individual to feel or be attracted
to another gender as some lore would have you deem "appropriate".
In most ancient societies these matters were never in question but
widely accepted as normal human conditions.