A pervert doctor invented the word “gender” (as now used) in 1955.
The entire “science” comes from an unethical experiment where he mutilated and molested twin boys, who committed suicide upon adulthood due to his mad experiments. And yet the fraud is still cited with authority.
Gender is a literary term and there are three. The three genders are masculine, feminine, and neutral. It is far older than some quack’s corruption in the 60s.
Combine that with society's "knowledge" about sexuality invented by Kinsey, based largely upon the behaviors of queers and felons, and it is easy to understand why society is so ****ed up.