Pretty much all of the Sci-Fi written by Ursula K. LeGuin features people more than machines. There are technologies in the stories that play a role, but the are described as vaguely as possible to support the plot. As a result, often her sci-fi stories feel more like fantasy.

Octavia Butler wrote the Xenogenesis series which features an alien “species” whose system of technology is entirely biological.

I mean… steampunk pretends to emulate modern tech all with steam power. Not only is it so absurd that it’s funny and enjoyable, but aesthetically when bathed in art deco, it’s positively gorgeous.

But in terms of story…. Shrug, there are probably tons of sci-fi writers that have touched this kind of storytelling. I think Alan Dean Foster maybe had something like this, and/or Piers Anthony, maybe a few others I read many years ago. No recollection as to what actual books, sorry.

Dune.

It’s called Dune

Children of Men would be a sci-fi without any significant technological improvements. Ender’s Game does have the Ansible, but it’s more a plot device than anything.

The Dune universe lacks computers, which is why spice is so valuable - does that count? Still has plenty of machines, but they aren’t the story

Alan Dean Foster has a series (Humanx Commonwealth) starting with Midworld. No special machines in the first 4.

Cachelot is excellent and is about sentient space cetaceans after forming a treaty with humans.

Midworld is basically Avatar.

Nor Crystal Tears is about the Thranx side of meeting Aliens (humankind) in first contact.

Sentenced to Prism is about the concepts of non-carbon life forms.

Must books cover elements of humanity and what is humanity.

Any sufficiently advanced technology is indistinguishable for magic

Probably not exactly matching your meaning, but in a round about way, Dune, post Machine Crusade –

It’s maybe not as evident without reading the series–which definitely isn’t a negative comment! I’ve enjoyed (almost) every bit of the truly shocking amount of Dune I’ve put myself through since the very early '90s, haha.

I’m, uh, mildly obsessive as well as critical of the SF I stand by, (just for myself personally!–everyone should like whatever they like!) but Frank Herbert, entirely, still remains in my top 2 favorite authors. You may enjoy all the books as a whole, if you’re looking for something less about ‘the machine’ itself, but how humans diverge from it and without it, but it’s…a lot, lol. And…well, I won’t spoil things. I just remembered it might negate my entire point. Oh, no. (ʘ‿ʘ)

Anyway! Regardless!

If you do ever get into full-ass Dune–and I’d recommend this “tip” to literally anyone–I’d definitely suggest audio books for the early works of Brian Herbert and Kevin J Anderson. They took a bit to get into their groove from informational to actually entertaining. The lore is honestly fantastic, beautifully done, but physically reading their earlier Dune stuff can be textbook without diagram tedious. Love 'em both for the work, but shiiiiiiiiite.

• ‘The Chrysalids’ and ‘The Midwich Cuckoos’ by John Wyndham
• ‘West of Eden’ by Harry Harrison

I’ve wondered about a sort of fantasy story with all the hallmarks of science-fiction. Maybe a wizard grapples with the ethical problems that a new spell would unleash if he were to use it. He could end famine for all time for his people, but maybe it makes every other land in the surrounding area inhospitable to life. Or something along those lines where a new “tech” will cause a major disruption with moral/ethical dilemmas, it’s just that the “tech” is some sort of magical device or spell, something very fantasy-based. Everything would take place in a medieval era, nothing high-tech at all, but the whole thing is structured like a sci-fi story. After all, medieval tech is still “high-tech” depending on your temporal point of view.

Anathem by Neal Stephenson

Stories of Your Life and Others by Ted Chiang

The Caves of Steel by Isaac Asimov

Cat’s Cradle by Kurt Vonnegut, Jr.

The Godmakers by Frank Herbert

Self-Reference ENGINE by Toh EnJoe

*Bonus: Low (comic series) from Image

There’s plenty of star trek episodes that are more about philosophical and societal questions than tech.

The bicentennial man by Isaac Asimov comes to mind. Which is about a robot, but in essence it’s about the philosophical question what it means to be human.

There’s Ubik by Philip K Dick, which is about about tech, when you get down to it, but in a very unique and un-tech like way.

Flowers for Algernon by Daniel Keys is not about tech, but the chronicles of a brain surgery patient that became extremely smart.

Hyperion by Dan Simmons is basically just “The Canterbury Tales” in space.

There’s plenty more stories that are not really about tech. You could try searching for dystopia themes, like “Maze runner” or “the hunger games” or “I am legend” or “wayward pines”

Try searching for authors who describe their work as “Speculative fiction” - that’s the way most of them don’t admit to writing low-brow schlock like sci-fi.

Also near future sci-fi tends to be a bit lighter on the “magical machine” plot tropes. Climate fiction might be worth looking into too, most of the near future books exploring possible global warming consequences aren’t all hopped up on magical technological advances.

Edit: also check out various books described as literary speculative fiction. Authors who want the intellectual cred of being a literary writer tend to land in the speculative fiction genre more often than not.