I would argue, rather, that the concept of gender has been co-opted and redefined by the cultural Marxists as a tool to try to force their unnatural model of human society down our throats.
Actually, I said that in my last post, albeit in a very convoluted way.
The cultural/temporal/dialectical roots to which I refer are strictly facets of American culture. My culture is shaped by the fact that I was born and raised in the San Francisco Bay Area, but have lived most of my adult life in Maryland. I gather from your previous postings that you are a pure New Yorker, born and raised. My temporal perspective is that I grew up in the 1960s and 1970s, and belong to the younger group of Baby Boomers. And my dialect is Northern Californian, mediated by Maryland influences.
What this all boils down to is that our cultural perspectives may be quite different, to the extent that behaviors/language usage that one of us finds perfectly ordinary and unremarkable might be deeply offensive to the other. So while you use the word “sex” to refer to biological gender, I find that usage embarrassing and uncomfortable and try to avoid it whenever possible.