Yeah, no, that's not how that stuff works.
First of all: your argument that the game's essentially relishing in its sadism or softcore pornography is flawed, as the mix between ultra dark elements and light-heartedness isn't done in a way that undermines either elements. The juxtaposition of the elements is done in such a way that the darkness of certain plot elements allows for catharsis, but the light-hearted elements (like the cardboard boxes and chicken hat) have nothing to do with all the narrative elements and are there purely for their conventional Kojima-ness and as (gameplay) palate cleansers. The dark narrative elements are the best thing Kojima has done in ages, as it's a sign of his maturity as a story teller; the best moments in this game would not have the same intense effect if the plot wasn't so damn real and heavy.
Also: be consistent, man. You can't say you enjoy the game's light-heartedness but then complain that Quiet looks too sexist. The reason we (collectively) allowed characters like Sniper Wolf and EVA was because they suited the arcadey, light-hearted, old skool video game tone of their respective games. Pick a side.
Anyway, I'm starting to get sick of the Quiet discussion. Not because of how much it pops up, but because most people don't seem to realize that the only reason they're still fucking discussing it is because of their own insecurity towards sexuality. Quiet's nakedness is contextualized, it's been leaked, it has a place within Metal Gear; deal with it. You don't have to agree with it, but trying to constantly justify your outrage towards it is nothing but a clear-cut sign that you have a problem with boobies in media in general. Grow up. Please. This is an ADULT game. With ADULT themes. And ADULT imagery. You might not enjoy adult imagery, but don't try to blame the game for it, especially since it has gone out of its way to explain it within its own universe.
This is a war simulator, guys. One which genius lies in its ability to both confront us with the nastiness of war (violence, death, sadism, rape, betrayal, etc.) and let us have our cake and eat it too by letting us shoot the mans with a variety of weaponry. It's a masterpiece, partially because it always manages to keep a clear distinction between those two things. Don't let your own inability to make that distinction allow yourself to get angry at the game. Get angry at yourself.