These topics are quite interesting to read through, even if they also tend to bring a lot of conflicting thoughts and emotions.
On the one hand, I do fully agree that the best possible depictions of sexually attractive male or female characters are those that match the surrounding context. This is something that a lot of games have failed at accomplishing. However, it's still valid to come up with various combinations of contexts within the same fictional world, not just limited to those based on strictly defined genre (or, for that matter, gender) lines. That requires a more thoughtful and careful crafting of a game's presentation and its implications. Most game developers just don't seem to put a lot of time and effort into thinking about this topic.
Therefore, it's also worth mentioning how certain character designs can still be judged as subjectively bad even within a fitting context. I believe another thread on this forum has already provided a platform for discussing how any given piece of artwork can either succeed or fail in terms of its own visual merits, beyond whatever degree of nudity, skin exposure or sexualization is involved. Art can still have inherent value in our eyes, one way or another, regardless of whether it happens to be considered clean or dirty.
On the other hand, I believe that the question of agency is a key part of the equation. I am going to argue that a lot less people would be mad about Quiet, regardless of her silly outfit, if the game's storytelling treated her much better as a whole. Not with respect to Kojima's almost literally incredible explanation for her lack of clothing, but in terms of improving her entire portrayal and giving it more complexity or relevance. As things stand, there's a couple of interesting themes being thrown around during the events of MGS V that you can connect back to Quiet, on paper, yet the game doesn't really attempt to give her enough attention nor agency to argue it somehow respected her as a person. She could be written out without requiring major changes to the plot (and yes, I know we can already tell this much in practice).
In that sense, I feel game developers need to focus on providing more options and variety to female players in order to continue addressing and eventually overcoming the problems discussed here. There can and should be many more female characters, including both sexualized and non-sexualized individuals, with both small and large active roles within a game's narrative, rather than just having a token girl or two. It's not a question of erasing all sexuality or sexualization. That's not even a realistic outcome.
I think most people realize that games are a reflection of the state of society, rather than the other way around. The act of changing games can only produce a very limited and marginal impact on society and culture, especially in the middle of such a fragmented gaming and media consumption landscape. Games have become more mainstream, but we spend less time playing each of them. There are occasional exceptions, yet I would suggest that every individual game, no matter how good or bad it is, has far less of a relative or absolute influence on its target audience in 2017 than in 1997 or 2007.
Even so, we still need to have more women as game directors, writers, character designers and creative personnel in general in order to let their voices, preferences, interests and concerns contribute to the game development process. Those who are afraid that listening to more women will lead to all games suddenly removing all sexy clothes are overreacting and also underestimating the kinds of deeper contributions that would have a more useful effect than that on any given game.