This is weird for me as a feminine guy, because I've pretty much only seen the reverse. "Feminine guys aren't real men/Feminine guys are trans in denial/'Traps' aren't gay/You're not gay if you're into feminine males because they're basically like women"

In fact one of the biggest reasons I don't associate with the LGBT or gay community is that I can't relate to them, because from what I've seen everyone either hates feminine males for existing, thinks they're a commodity/object/quick fetish fuel and not people, OR they think we all have to be "the sassy gay best friend" trope, or that we're secretly "trans girls." In my experience the LGBT is not welcome to gender non conforming people, especially feminine males, unless they are walking plastic surgery assholes like Jeffree Star and James Charles who's entire identity is "I'm gay and obnoxious and don't act like any sane real person would."

A lot of gay communities are "masc4masc" too and that's another reason I don't believe I'm welcome, I just don't fit. This also includes 18+/NSFW spaces... sometimes I feel like the only "fem4fem" guy because I can't seem to find content tailored for feminine guys by feminine guys... it's always NSFW masc gay subreddits, or some weird "daddy top seeking femboy" (yuck) thing, or gay porn that focuses very heavily on masculinity. Which is fine, and I understand why its most popular, people like me are outliers, but thats my reason.

"Straight acting" is funny too because I would say that the obnoxious, only feminine-as-a-kink guys are more "straight acting" (or trying to be) for attempting to emulate heterosexual, sexist gender roles by "being the woman in the relationship" while seeking out masculine men.

Also what context is one's behavior judged exactly? I'm not at all masculine and I'm very open with my femininity. Buuut I don't have "the gay accent" or ever talk about my sexuality, and most people IRL assume I am straight now. Am I "straight acting", or does simply wearing eyeshadow mean that I am "gay acting"? It's dumb.

To answer the main question, I don't think there was a slope. I've always seen a lot of bad in LGBT, it just goes through phases of different flavors. I don't think any of this is new in my opinion, I've certainly seen it for as long as I can recall.

Edit: Also in my experience, stereotypical "feminine" guys are nasty to actual GNC males, I've had a lot of them attack me for not being the "right" kind of feminine (aka not stereotypical and sexist, sexualized behavior) and call me a bunch of names. When people call me degrading shit I don't like, such as "twink" or "bottom" or "queen", it's usually one of those hyper-feminine annoying guys who still thinks typing "sksksksksk" is funny.