I browsed /g/ as a teen, watched lain and everything, but have since decided to consciously distance myself from this culture, to a certain degree because there is a sort of implicit "sexism" (in some broader sense) that I don't feel comfortable with anymore. The longer I stay away, the more obvious things like the way they draw faces and bodies, the often infantilizing postures combined with a kind of sexualization is. Keep in mind that drawn images can easily exaggerate human features that are not healthy or even anatomically possible, but that still serve symbolically as sexual indicators. This has become worse and worse over time, because fan service is good advertisement for publishing houses. Take a look at
https://en.wikipedia.org/wiki/List_of_slice_of_life_anime and compare how the style has changed since the late 90's up until today. I think it is a lot more homogeneous and the appearance is more formulaic. Part of this might be that computer animation is more common place, but the other one is that a sense of beauty has been reduced to a mathematical problem of relating various proportions. It is also because I was part of this culture, that I know there is an explicit and intentional sexual aspect to all of this.
Reflecting upon my own impressions and how these changed, I am more conscious of these points and find it hard to ignore them. Assuming that I am not totally mistaken, which of course might be the case, knowing that others don't see these things pains me. More so when someone like the author of the link publically stands by it.
But you are right though that not every image is like this.