OK, haven't played this game quite yet but have kept up with the whole discussion around it, and I just wanted to comment about some of your statements. So before you comment about a "non-answer" again, I'm aware I'm not making an argument about Ground Zeroes (there's plenty of that out there from when the game came out), I'm just explaining how people MIGHT disagree with you and why that's OK.
As for your fir
st point about her not being a prop because the main character wanted to save her life: Prop characters are used all the time as the "goal" of the hero. Their existence is the story is to give the main character his motivation, rather than them being their own character, they are reduced to an object. I can't say if I feel this way, but some people certainly did.
The second part I highlighted is a big assumption on your part. And even IF everyone who felt she was a prop hadn't played PW (a game that came out almost 5 years ago that lacks indication that it's part of the number sequel series) or played every (optional) audiolog,
it is still absolutely a flaw for many people in a story if the writer didn't bother to humanize a character during the course of the main story of the sequel.
And you're comment on shock value: of course shocks can be used as a writing technique, what matters is the context of the "shock" and whether people think it's done well. "Ew, it's gross" is a comment on what people think of the maturity (or lack thereof) of this particular twist. Unfortunately I've had this "shock" spoiled for me, but it doesn't surprise me in the slightest that there are people out there who consider
a pretty dumb shock at best and offensive at worst.
So yeah, people have opinions they've been explained, (I know since I've read them or listened to them in the past back when the game first released), and frankly they seem no less valid than any of the points or opinions you've shared.