I'm not an Amiga'n. When I was a kid in the late 1980s, a friend of mine had some Amiga, and I enjoyed a couple of games he let me play on it, and that's about the extent of my experience since then.
So, I'm finding it difficult to understand what this project actually is: Is it hardware for running original Amiga games and apps, or has there been a continuing user community and SW development effort in Amiga-world that us PC-heads are just not aware of? And that is interesting and different than copycatting advances from non-Amiga environments?
The Amiga has become a Ship of Theseus situation. After the 68000 CPU series was no longer developed, third-party expansion boards were developed to add a PowerPC CPU to existing Amigas. AmigaOS 4 was developed to run on PowerPC, and later PowerPC Amiga motherboards were developed which didn't require original Amiga hardware at all. There's also MorphOS, an Amiga-compatible PowerPC OS, and AROS, an open source OS which runs on x86.
There's a substantial Amiga enthusiast community to this day, which is the main market for this stuff. The various "new Amiga" platforms can only run original Amiga games via emulation. There has been plenty of development in the Amiga field, including new games, software and hardware expansions, though it is a niche hobbyist thing and mainly for people who love Amiga. You can find more information on YouTube.
That's what sort of confuses me.
If you're no longer running a 680x0 and the custom chips that defined what an (original-series) Amiga was, and you can't plug in any of the historic peripherals (I don't even see a 9-pin joystick/mouse socket!) why bother with PowerPC in $current_year?
I can sort of see the story for projects like the "Denise" board where it's basically a way to create a new hardware 68k Amiga (although modern replacements for the Commodore silicon might be desirable, so we aren't just desoldering/desocketing the same 30-year-old chips again and again).
But if you've already given up the main aspects of classic Amiga hardware and chosen emulation as the road forward, cheapest commodity x86-64 or ARM products would be fast enough to emulate pretty much any mainstream 680x0 option and the custom chips. I could see a small niche for a PPC coprocessor accelerator for the small sliver of "PPC-native" software if the current emulation isn't fast enough.
Well, the Power architecture generally is certainly something I would have liked to see more love for. A few years back I heard about it (again) due to its supporting GPUs as "first-class citizens" w.r.t. access to system memory. Or at least, some OpenPower systems allow for that.
I'll try to look this up on YouTube, and thanks.