Yeah. I wasn't sure how much sex constituted sex crazed from the original post; I think it's hard to do a gay coming of age without anything P-13 without it coming off as sort of round about or being fairly disguised. There are some completely chaste examples, but they're rare since, well, sex is kind of a part of the experience of coming to terms with being homosexual. So, there's a few good books which are really well written but there's a lot of sex going on.
For Webcomics? I think you anwser it yourself. If you publish a thinly disguised lesbian or gay porn, you'll be tossed in the pulp/romance section without a second thought. For Webcomic artists? It's "daring" and can actually get buzz going about being progressive, while also pulling in people who want to see them kiss. Webcomics have always been closer to their fanbases, so it sort of makes sense that they'd be more open to listening to shippers begging for two blokes or girls to bump uglies where a TV show is more worried about mass marketability. There's also a lot of shittier webcomics out there that are highly visible. It's definitely a problem that authors avoid "icky" pairings beneath a progressive veneer but it's one I've bitched about and I can't say I've ever gotten a satisfactory anwser as to why so many gloss it.
On the other hand, I also think you're standards might be a bit high as well. For instance;
I'd at least argue that MGDMT wasn't bad about it. It wasn't dropped immediately despite it being something the author has long cared about. The idea that the Commander is willing to swing both ways and say so casually feels like 100% in character for him.
Supernormal Step, I feel like I could kind of see it coming and it didn't feel like it was just dropped in. On the otherhand, I'll agree that she was totally willing to drop the tumblr term and definition was awful writing and made it feel like it was a blantant move to appeal. I'd argue though if she had said something like "Look, I'm flattered but I've just never been into that sort of thing. With anyone." then it'd have felt perfectly organic.
GKC was shite though, I'll concede. I definitely put on a few examples of varying quality since ehn, I can't predict what others like and it has its defenders here.
Cuanta Vita miiiiiiiiight meet your standards though. It has a fairly rape-y character who was creepy as fuck and one character does a homophobic to homosexual flip, but where GKC felt like a cheap pandering move from a fanfic (Oh Kat, I was only nervous! Let us make lesbian babbits!), I actually bought and believed CV's one. Maybe because it was more central and developed a fair bit. Maybe you still won't go for it, but it might just do for you.
Also why the fuck is polyamory the new thing among SJWs?
My best guess? It's controversial but doesn't directly hurt anyone. So harm principle liberalism. Also, a lot of the arguments for homosexuality can be applied to polyamory with only a few words swapped around, if you're willing to ignore the context. Therefore, it's a new cause they can clammer on about as more and more people are fine with gay marriage.
What. The fuck. Am I reading?
I maintain that some of this could be handled better and actually be good if there were a half decent writer. I'll explain it in two parts;
One of the characters is basically a cyborg reconstructed from bits of a girl who died young. She's got some GhostInTheShell existential shit going on, moping about being a hollow shell of a human and etc. She's cut herself off from people and basically is hiding away from the world. The premise of the comic gives her an odd couple roommate who is now dragging her out to a party to make her less mopey.
This could be done well, I'd say. Where it gets shitty;
The poster is referring to the bit where the cyborg's roommate/the protagonist ditches her so she can get into the pants of some stranger. Basically ditching her introverted cyborg friend with the cast-nympho, where she is too shy to say "fuck off". She then meets a girl with an artificial vagina (I think) and hand, and because of this girl, the cyborg suddenly feels better about having been built from stratch from a dead chick or something. Also, they are all naked for no real reason.
I'm hoping you can make sense of how I phrased my summary, but the plot is still wierd and nonsensical. Still, some of the world building could make a sort of cool Brave-New-World styled surreal world of hedonism and questionable humanity. I think sometimes that this is the goal. But the author really really fails at conveying it if it is.