That's a big part of it, yeah. A ton of female characters in fantasy fiction, whether PC or NPC, are motivated by being sexually assaulted. Red Sonja is a great example. Where their whole schtick is "No other man will have me but that I choose it" or the ever popular "Only someone who defeats me in combat will have me"This seems like an unjustified conclusion.
I can't imagine that the all male groups I mostly played TSR D&D with in the 80s and 90s were rare outliers in not making sexual violence and misogyny integral to the gaming while still having plenty of violent actions in our gaming.
If you saw frequent use of rape and violence against female NPCs in your gaming that is pretty horrible, my condolences on the bad experiences.
Orc raiders were often stealing women to assault and impregnate to create half-orcs. Even the Army of Darkness had skeletons kidnapping women with their chests exposed, presumably not to bone with since no one in the army -had- that bone...
It's a pervasive trope. And that's not even getting to your party hanging around in a tavern and the fighter making an offhand comment about swatting the barmaid's backside or rolling to check if there are any hot chicks there "'Cause I wanna doooo them!"
Just a ton of subtle and overt sexism that becomes the background radiation of a ton of D&D games.