I think someone needs to explain to this person what "science" is. If it's mere opinion, then why do we need scientists?
"It is counter to medical science to use chromosomes, hormones, internal reproductive organs, external genitalia, or secondary sex characteristics to override gender identity for purposes of classifying someone as male or female.”
https://www.heritage.org/gender/commentary/transgender-ideology-riddled-contradictions-here-are-the-big-ones