I say this with genuine, and I do actually mean genuine, respect, but the point of the original post wasn’t to put an equals sign between fluff/cozy fic/coffeeship AUs and fascism. The point of the post was to draw attention to the very real push toward a "cultural hegemony" that happens every time fascist ideology takes hold of a culture. The rest under a cut for length.
In this case, it is white Euro-American Christofascism that demonizes and criminalizes any sexuality that is not reproductively-driven sex between cisgender heterosexual men and women. It is Christofascism that calls any sex not cishet sex for the singular purpose of procreation (or any physical or psychological deviance) degeneracy, which is a buzzword that eugenicists have used for decades to justify conversion therapy for gay kids, forced sterilization of mentally ill people and POC, and the illegality of gay marriage.
Christofascism hates any violence that is not the violence of its own against The Other (which is anyone not drinking the kool aid). It weaponizes “family-friendly values” to wash out any nuance and moral complexity from a piece of art. It weaponizes “family-friendly values”, a distinctly white American Christofascist construct, to delegitimize, suppress, and erase any story that does not conform to its standards. Which includes… a lot.
If you look at the larger trend of mainstream (film) storytelling over the last 30 years, you can see this clearly. We had films, shows, and stories in the mainstream that would never have been able to be made today: Full Metal Jacket (1987), a viciously, violently antiwar film. Leon The Professional (1994) about a middle aged hitman who befriends a precociously sexual preteen girl and teaches her how to kill people. That 70s Show, which was much more recent (ended in the early aughts) but still showed minors drinking alcohol and smoking pot onscreen. Entrapment (1999), a film where a young woman in her 20s or very early 30s gets sexually and romantically involved with a man in his 70s. Contrast that with today, when the most “edgy” thing in the mainstream is an irony-poisoned superhero movie that relentlessly queerbaits its audience but makes it painfully clear that No, Actually, They’re Not Gay, They’re Just Doing It For The Lols. No shade if you genuinely enjoyed Deadpool and Wolverine, by the way. I did too; thought it was funny as shit. But it's also very much a product of its sociocultural time, and the time is Kinda Bad.
Thankfully we do have people still making genuinely Good stories with heavier, more complex, more morally grey themes, but my point stands.
So was everything better back then? Oh hell no. Sexism and racism were also onscreen full bore, so in that way we have moved forward. But my point is not to say “back then things were better”, which is, itself, an authoritarian dogwhistle. My point is that rightwing Christofascist authoritarianism, with the help of corporations and governments lacking the political will to oppose it, has driven much of the nuance and humanity from mainstream storytelling to serve its sociopolitical agenda and it has begun to show in the downstream culture of fandom.
This is where authoritarianism on the left wing rears its head: why you see people getting kicked out of discord servers for offenses that would get them nothing more than a hard look in real life. The insistence that shows up on both sides of the political aisle: that fiction is reality is fiction. On the right, this looks like "violent video games are turning my kid into a murderer". On the left, this looks like "this person wrote a fictional minor having sex with a fictional adult, so the person is a CSA apologist in real life and should die."
That is the truly reactionary bullshit in this scenario.
I myself, a frequent creator of exactly the kind of content this authoritarian fandom culture hates, have been kicked out of several fandoms and have received several death threats for writing things that violate this purity culture that has developed in so many fandom spaces nowadays. My friends and people I know have been victims of the same. And it has only gotten worse over the last 15 or so years.
This purity culture is what the original post is meant to talk against. The purity culture is performative, closed-minded, and (left-wing) authoritarian. It finds any art that does not meet the purity standard (see above) disgusting, degenerate (there’s that word again), and unfit to exist. It incentivizes simple, nonthreatening stories; stories that do not require the reader to think critically or face any kind of moral conflict. In the mental landscape of the authoritarian, Moral Good is cozy, comfortable, white-coded, simple, and does not force one to confront or examine one's morality or ideology. Moral Evil is complicated, nuanced, scary, colorful, and defiantly deviant.
But again, this does not mean that if you write, read, or enjoy these kinds of stories, that you are a fascist. It just highlights this false equivalency between Moral Evil and thematic darkness/deviancy.
I hope this helps make sense of the original post a little.