I was referring to the combined damsel in distress premise plus mercy killing requirement. That's a trope I've always found particularly offensive. The first game I know of that used it was Ghosts n' Ghouls way back in the '80s, and then Duke Nukem in a much bigger and more extreme way in the '90s. In the 2000s though through really 2012, that time frame, it became popularized because by then consumers were used to the standard damsel in distress scenarios, so developers started trying to add "dark and edgy innovations" to them instead of just trying something genuinely new. That trend really began with Breath of Fire IV around the turn of the century and encompassed a LOT of games for a long time after that. Twilight Princess was one of them, although Nintendo's variation was more light-handed than most, as Zelda gets revived in the end and whatnot. Still, it struck me that even a conservative company like Nintendo would opt for that route (especially given that they had seemed to be on a different, and what I'd consider somewhat more positive, track with the character over time). That in my mind just cemented how normalized this particularly misogynistic line of thinking had become in gaming.
The mercy killing "twist" is usually narrative excused by the girl or woman becoming demon-possessed, thus obliging you to kill them "for their own good". Think about that for a minute. That's the literal definition of demonizing someone.
I found your intro intersting because it was quite similar to my own gaming/life history with the games I was in to, a break in young adulthood as I discovered girls and parties, and then a return to it a little later on and enjoy gaming now as much as ever. It really is a fun thing that suits my current lifestyle with a wife and baby on the way.
I couldn't help pick out this aspect of your intro and subsequent response though. It's become a recent trend in feminism to attack certain things as misogynistic which are not misogynistic. I find it quite tiresome. A damsel in distress story is not sexist. Neither is mercy killing of a posessed character. If a character was killed because they were a woman, that would be sexist.
My wife is a strong, successful, professional woman. We both have great careers, she earns more me while traveling the world doing amazing things. But she also enjoys many traditionally feminine things, and she is not "tough" when it comes to phyisical confrontation. She enjoys a good knight in shining armour saving a threatened damsel story. Perhaps you prefer the action hero to be a female as that relates to how your brain works. That's perfectly fine, but the mistake is in thinking that it is somehow sexism if that's not the case. What you're feeling is more likely a feeling of non-relatability than sexism.
I would agree that some titles in the late 90s began having morally-lacking themes. Duke Nukem has sexist elements, and the dawn of titles like GTA which prided themselves on freedom to do evil if you choose changed games forever. It was a shift in entertainment in general, where you saw movies like Saw shock audiences or the WWE going from having Hulk Hogan never hitting a woman to having the Rock lay the elbow down on Steph McMahon and both male characters were protrayed as heros. That was the turn our fiction took, for better or worse.