Generation Amiga covers Commodore Amiga news, history, software, the demoscene, and new hardware and projects.
HN links it for Amiga history, such as the Babylon 5 render farm of A2000s, and for new Amiga projects like ApolloOS.
It's not so bad if you look across all Amiga-related development.
Is the PowerPC hardware for OS4 expensive? The high end devices like the X5000 certainly are, but entry level devices like the A1222 are coming out soon, and are priced around £500, which seems like a level many hobbyists would feel comfortable with:
https://www.generationamiga.com/2017/02/10/preview-amigaone-a1222/
It's also possible to run OS4 in WinUAE, so it's possible to try out OS4 before buying new hardware.
For an even cheaper route, the other two next-gen Amiga-related operating systems, AROS and MorphOS, offer cheaper hardware options than OS4. MorphOS runs (aside from a few niche devices) on PowerPC Mac hardware:
http://www.morphos.de/hardware
You can easily get a working PowerPC Mac for less than £100 on eBay.
AROS is even cheaper still, as it's open source and runs on standard x86 hardware. You might spend a bit of money on a supported network/sound/graphics card if the devices that came with a PC aren't fully supported, but otherwise it's essentially zero cost to get into.
With regards to the Amiga IP, things are looking up, the rights have mostly been acquired by Cloanto now, which is one of the few companies actively supporting the Amiga:
http://www.amiga-news.de/en/news/AN-2017-04-00033-EN.html
The irony is that Commodore in the US pushed it a lot harder as a business / graphics workstation, but they'd ruined their dealer network a few years before and never really managed to build it up again, so they struggled to get it into professional dealers, while they failed to market well to the gamer market.
Meanwhile, Commodore UK achieved most of their success by making games bundles that the US was very reluctant to try to push.
E.g. the Commodore UK "Batman pack" in '89 was near legendary [1][2] in its ability to drive Amiga sales.
Commodore UK did well enough that they tried to assemble a consortium to buy Commodore International when their parent company went bankrupt...
[1] https://www.generationamiga.com/2021/05/09/how-batman-changed-everything-for-commodore-amiga-computers/
[2] https://www.pczone.co.uk/back-to-the-amiga-500-batman-pack-30-years-later/
The guys that created the vampire accelarator boards for Amiga now have a open source (ish) OS called Apollo OS. It has a hardware abstract layer which hopefully means there will be a decent x86 port.
https://www.generationamiga.com/2020/07/11/apolloos-a-new-open-source-amigaos-compatible-distro-without-the-legal-issues/
There was also Icaros and Morphos but I am not sure what going on with those.
It seems entirely plausible to me that three letter agencies could also have done render farm type things like this: http://www.generationamiga.com/2020/08/30/how-24-commodore-amiga-2000s-created-babylon-5/
(I think this is a subset of your comment rather than an extension but Babylon 5 reference ;)
Not completely unheard of but I get your point :). Babylon 5's pilot's animations (and I believe opening credits) was rendered in 1993 on sixteen souped-up A2000s, each with 32 MB of RAM.
https://www.generationamiga.com/2020/08/30/how-24-commodore-amiga-2000s-created-babylon-5/
Haiku OS[0] is a BeOS inspired OS, though I do see some articles about a port of it to Amiga hardware.
[0]https://www.haiku-os.org/
[1]http://www.generationamiga.com/2017/09/03/haiku-os-for-amigaone-500-computers-68k-port-in-development/