I like:

Technology Connections. Alec is a refrigeration cycle enthusiast from the American Midwest in a tweed jacket who talks about gadgetry. He’ll change your understanding of dishwashers.

History For Granite. Join him to explore ancient Egypt. A no bullshit no ancient aliens channel focusing on old kingdom Egyptian monuments, particularly the pyramids of Giza and Dahshur. His hot takes include “The ascending passage of the Great Pyramid is built of lower quality limestone, possibly because the higher quality Tura limestone used for most passageways wasn’t available. As the passage ascends, you can see the work getting more consistent and gaining quality, as if the masons were gaining skill working with this inferior material.” And he casts solar eclipse quantities of shade at Zahi Hawass. It’s hilarious.

Cathode Ray Dude. A computer and video hardware enthusiast from the Pacific Northwest. He’ll find some electronics artifact and explore its quirks and features, including a whole series on weird old laptops.

Paul Fellows. Bri’ish astronomer type who delivers short-ish briefings on astronomical objects. “Once Around: The Large Magellanic Cloud.” I’m getting to where I prefer his content to SEA or Astrum.

TierZoo. Animal documentaries in the style of video game commentary. Animals are player characters in a massively multiplayer game called Outside. A typical video will be titled “Are snakes OP?” and he will rank various snakes on a tier list. “Next we have the rattlesnake. Rattlesnakes have spent evolution points on the rattle ability, a mid-level intimidation and area denial attack intended to evade encounters with carnivore mains.” The fact he’s been able to keep up this shtick so long is the most entertaining part.

While not exactly what you are asking, check out Nebula as it has a lot of long form content that is not slop because they actively monitor it.

Don’t see “Half As Interesting” listed here. His stuff doesn’t usually go super deep, but I’ve learned a lot from him.

And just recently he was accused of using AI for a thumbnail and this was his response:

Even if you can’t afford Nebula, I recommend browsing its explore section, because many of its high quality creators and videos are also on YouTube. The following are some of my favourite creators on YouTube.

30 minute animated documentary-style videos: LEMMiNO, melodysheep, fern, Hoog, neo, PolyMatter, Imperial, Cipher, Real Engineering, Mustard

Shorter explainer videos: Posy, Kurzgesagt, PBS Space Time, Sciencephile the AI, minutephysics, Steve Mould, Half as Interesting

If you are interested in (astro)physics, here are two channels which i enjoy and can assure for their correctness on research topics:

Dr. Becky Astrophysicist talking about what’s happening in space from planets currently visible by nakedness eye to new impactfull research papers. She explains everything in an approachable way.

Angela Collier Theoretical physicist, makes long story telling videos about physics and societal topics surrounding research. Most videos are >50 minutes, some are more than three hours. However, they often stray from the original topic.

For some talk about philosophy, I can recommend Philosophy Tube. Most videos are somewhat short of an hour, but explain some philosophical topic in an approachable and interesting manner. Just don’t be detered by her extraordinary costumes for each session. I think she research the philosophical questions quite well.

allegedly Scary Interesting uses no AI generated content

A few channels I like that I think should fit. AFAIK none of them use AI whatsoever.

Stefan Milo (Prehistory/Archaeology)

Told in Stone (Ancient History)

World of Antiquity (Ancient History)

The Pharao Nerd (History)

Trey the Explainer (History and random topics)

Anton Petrov (Space and Science)

Big Joel (Culture/Media)

STRANGE ÆONS (Internet culture and random stuff)

More perfect union, according to Nicole, Zac rios

3 of my favorites in last few months.

Darknet diaries is the shit for podcasts. Also on YouTube.

pbs eons, there are bunch of channels related to this one, some people on reporting on paleontology/new discoveries, or bio, i like how some people in the comments try to accuse the channels of AI without actual evidence. almost all the influencers AI for thier thumbnails, which i find cringey.

i would be careful watch pbs terra though, because there seems to be some sort of misinformation(like the alleged experts are speaking from an misinformed point of view), like how they are trying to save american chestnut species being devestated by blight, but doesnt go into detail(omit) why they are using the chinese hybrid to prevent disease, which makes it not a natural species since it was the chinese one that spread the disease in the first place, same goes with the devil holes pupfish(claims they are saving the species but doesnt really say why its being hybridizing with another species). there is just something off about that channel that doesnt have with the other pbs channels.

LEMMiNO’s production quality on his mystery documentaries is brilliant.

Ahoy mainly focuses on aspects of video game history and video game weapon design. I love his voice.

3Blue1Brown for pure mathematics.

PBS and Nova are good. Science Channel as well. Most vids are short but they put out some banger full length documentaries every so often.

History Time is also really good. The length of the vids can be hella long.

The History Channel has some cool stuff too.

No one seems to have mentioned Steve Mould.
Super specific topics, interesting (to me anyway) and definitely no slop.
Edit:mentionded?

Not sure if these are what you’re looking for, but:

• Dr. Becky [professional commentary on astronomy and astrophysics]

• Anton Petrov [professional commentary on astronomy and astrophysics]

• What’s Going On With Shipping? [videos about the ins and outs of international maritime shipping]

• Not Just Bikes [focuses on the many ways urban infrastructure can be improved]

• Sampson Boat Co. [~seven years worth of videos where Leo rebuilds a 1910 gaff cutter from the keel up. Currently sailing it back to London to participate in race the same boat won a century ago]

• Primitive Technology [builds cool things with sticks, mud, water and pond scum]

• Bad Obsession Motorsport [bought an old mini-cooper and shoved an engine from a Celica GT-Four into it]

• Practical Engineering [a practical look at engineering projects that most people ignore, mostly because they're underground]

• B1M [videos focusing on large mega projects like tunnels and nuclear reactors]

• Jay and Mark [map guys that rightfully complain about Londons infrastructure]

• Florian Gadsby [skilled (practised) potter that makes really satisfying pieces]

There are also channels that are focused on the war in Ukraine and related international shenanigans (in order of avg. video length):

• Perun

• Denys Davydov

• Reporting from Ukraine

• Suchomimus (poor chap made a channel to nerd out about dinosaurs, then the Russians attacked…)

Also check out ytch.xyz; It serves videos from a curated list of channels such that it behaves like cable television.

Also also check out nebula.tv if you can afford it.

I’ve enjoyed DW Documentaries since I found them on a now defunct community TV channel back in the early 2000s. The format is the same now as it was then, so if they’ve worked in some AI slop, I haven’t noticed. Topics are varied - science, history, politics, the environment, how local traditions of varying places cope with change - as are the run times.

Some examples:

Zanzibar - Island Paradise in Flux

Father Unknown? Life as a Sperm Donor’s Child

Organic Farming as a Career Choice - Italy’s Young Farmers

Neutrios: Do They Reveal the Secrets of the Universe?

The Swiss Bar Fire Disaster - Life After the Nightmare

Toxic Colonialism: Secret Chemical Warfare in Algeria

Strong Women: The Fight for Self-Determination

Muscles - More Than Power and Pumping Iron

Final Days Full of Life - Hospice Stories

Opioid Crisis in the US Part 01: Business and Addiction

Opioid Crisis in the US Part 02: Business and Addiction

Veritasium

Fren

Johnny Harris

Compterphile

3blue1brown

tldrNews (several channel each for different region)

RealLifeLore

Money and Macro (actual economist, not finance bro)