Pern -- starting with the Harper Hall -- was one of my childhood SF book series. I didn't read all of Anne's output, let alone her son's, but a fair bit. Mari Ness on Tor.com is
re-reading Dragonflight, with interesting analysis; part two talks about some of the feminist aspects.
The reviewer's part one was odd, though, claiming "Weyr Search" started as fantasy and was diverted into SF. It would be interesting to see the original text in Analog, but the Internet fails me. She cited dogs turning spits, Hold as castle, swords, Lessa shapechanging...
Pern was always obviously SF to me, dragons or not; the first Pern words I read were the preface about the golden G-type star Rukbat and the lost colony around it. A commenter alleges those words were in Analog; certainly they're in my copy of Dragonflight, which I re-read today.
As for the other elements: there are dogs ('canines'), lashed to a spitrun; sounds like a treadmill or capstan rather than dogs on hind legs. There are castle-like aspects to the Holds, ramparts and towers, but the Hold proper is clearly carved into the cliff, even in the first part of the book. There are mentions of sword hilts, and later of swords, but Fax and F'lar duel with knives -- maybe neither brought a sword to dinner.
Lessa is clearly a powerful telepath, but the text really does suggest an actual illusion rather than mind control:
"as she shifted her regular features into an illusion of disagreeable ugliness."
done while F'lar is aware and staring straight at her. Lessa's mental nudges are usually on the unwary, and she's described earlier as blurring her arm when she notices F'lar looking at her. OTOH an illusion power seems extravagant and subsequently unused, while Lessa is telepathic through the book.
There are other oddities. F'lar's guest room has hangings:
‘The many-colored hangings were crowded with bloody battles, individual swordplay, bright-hued dragons in flight, firestones burning on the ridges, and all that Pern’s scarlet-stained history offered.’
Yet it feels as if Fax has invented conquest, so what battles?
F’lar fantasized about forcing tithes by firestoning, but shortly thinks that dragons would never hurt a human (except at hatching, poor things.)
Other observations:
Dragonriders have their own empathy: "She had had to learn that, although it was her nature to seethe, she must seethe discreetly. Unlike the average Pernese, dragonriders were apt to perceive strong emotional auras."
When the watchwher kills itself for Lessa, the dragons mourn it as one of their own; F'lar calls it a cousin; Mnementh says basically "no way! we were just honoring the sacrifice." I know they are in fact related... I suspect McCaffrey was in fact winging some things, like the social history of Pern, but had long ranging Plans for others.
Mnementh is a lot chattier and more proactive than I remember, including being politer about Lessa's name than F'lar ("that girl", even after sex with/raping her.) He's also capable of sarcasm:
'"Back to Ruatha?" F'lar repeated the words stupidly; the significance momentarily eluded him.
It certainly does, Mnementh agreed'
There's no religion, but both Lessa and Larad feel some of their thoughts or actions are 'heresy' or 'blasphemy', like wishing for Thread instead of Fax, or marching on Benden Weyr.
Even Manora doesn't tell Lessa *why* she's afraid of Lessa leaving the Weyr before Ramoth's flight, F'nor's the only one to give her a clue.
The Weyrleader system seems a stupid form of government, but sometimes the winning bronze is the one the Weyr wants, rather than just the strongest bronze. Though there's also "like dragon like rider".
The whole time travel plot is still brilliantly handled.
As Mari notes, when F'lar falls into despair, they send for Robinton, whom he hasn't even known for long, not some local-Benden friend.
Besides the preface screaming THIS IS A TERRAN COLONY PLANET, much of the book (and series!) is pretty strongly SF in feel rather than fantasy. Yes, dragons and knife fights and Lords, but also rediscovery of tech and even new advances.