So Jason just puts out his videos about 4 days early on Nebula. He's done a small number of Nebula bonus content videos, but not very many. If you like his videos, you might also like CityNerd, Stewart Hicks, City Beautiful, RMTransit, and Hoog which all also cover urbanism.

The HAI crew also operate the Wendover YouTube channel, and under that brand have released a bunch of really good documentaries, including the incredibly moving "Final Years of Majuro". There's also the channel "Extremities" from them, which "brings you the stories of how and why the world's most remote settlements exist". They have their game show, Jet Lag, which is really good, but I think that's on YouTube on a delay; they've recently also announced an upcoming series called "The Getaway", but other than the name and being from that crew, no more is known about it. Completely unrelated to them, there's the channel "neo", which I find satisfies much the same itch as HAI.

For tech news, there's The Friday Checkout, OzTalksHW, and TechAltar, but I watch none of those so can't comment precisely on their content.

No explicit privacy advocacy I'm afraid.

For science, there's Minute Physics, The Science Asylum, and Real Science which are their ones most similar to the ones you listed, but there are also a whole heap that do science from a different angle, like Atlas Pro, which uses real paper atlases as a framing device for talking about world geography; Tibees, who talks through scientific papers; Tier Zoo, who teaches about animals through the lens of video game logic; and Simon Clark, who is primarily focused on climate change through the lens of what science and technology we can use to help prevent it. I still watch and love Stand Up Maths and Steve Mould on YT though.

Not sure I'd ever say Lemmy has a "liberal" bias. More explicitly anti-liberal, tbh. But still, Nebula has TLDR, who do an impeccable job of producing a BBC or ABC-style news show with an explicit goal of leaving their own personal biases at the door and creating a show that avoids bias as much as humanly possible. Their semi-regular "The Editorial" is excellent, with them going over the mistakes they made and issuing corrections. There's also J.J. McCullough, who I don't watch, but have been lead to believe is a right-wing (but not far-right—more the sort of traditional conservative you might have typically expected before the 2000s) creator who seems to cover things in current affairs. And just recently they've added a new channel called Morning Brew, which I'm still trying to get a read on, but seems to be news primarily with a business focus. They've also recently announced a new news division, but we don't know exactly what form that's going to take yet or what sort of content will be coming out of it.

As far a misc entertainment, it's a very personal thing that's hard to give recommendations for. NileRed is listed under the science category, but his videos are often so bizarre that I'd say they're more like light entertainment. There is a huge amount of stuff covering media criticism, some with very serious tones, some much more casual; some looking at the art through specific lenses (there are a couple of queer creators in particular), others who take more of a film production bent, and ones who view it through the lens of pop culture. The film and media categories are probably the strongest part of Nebula. There's edutainment like Extra History. I have never had an interest in professional tennis, but have found CULT TENNIS to be a shockingly interesting channel (one of the ones I discovered through Nebula). A whole bunch of music channels like 12tone, Mary Spender, and Polyphonic; personally, I find them all far too focused on modern music for my tastes as a classical fan. Also technically listed under the "music" category is Tantacrul, though really I'd say many of his videos should be must-watch for anyone doing any sort of software UX design, even though he's specifically focussing on music notation/composition software. LegalEagle is weirdly categorised under "news", which I guess makes sense because a lot of his videos do cover current events, but fundamentally I personally view him as an entertainment channel who talks about the law. If you're a gamer at all, Razbuten is excellent, especially his "...For Someone Who Doesn't Really Play Games" series, where he introduces his wife, who is a non-gamer, to various different genres of games.

Personally, I couldn't ever replace YouTube entirely with Nebula. There's just way too much stuff on YT, and their discovery algorithm has gotten so good. They're really good in some niches, and much weaker in others. Some of the niches they're weak in, they're pretty obviously never going to enter. Live-streaming gaming, for example. But others they're expanding into all the time. When I first joined, they didn't have a single urbanism channel, and now they have most of the big urbanists on YouTube. These days Nebula is big enough that I have to check a couple of times per day to be sure that, if I look at the "latest videos" section of the front page, I don't miss anything entirely. (Though there's always the dedicated latest videos page if I did miss something from the front page.) Latest Videos has been a great way that I've come across entirely new channels and even niches that I wouldn't have thought to be interested in before. It's big, and varied, and growing a lot. I think it'd be hard not for someone to get their money's worth from it.