The word's been around for nearly 1000 years, and for half of that has explicitly been synonymous with 'sex' (biological category, not the activity).
What you're referring to is the concept invented by John Money in the 1950s, before postmodernists published their works (1960s), which then merged with feminism and communism and racism to become 'intersectionality' by the end of the 1980s.
Your ironic attempt to call out my 'ignorance' is really cute, though.