"There is no and will not be any new Amiga computer". Fair enough, but what we've got here is a subtley of naming when we compare it to the RISC OS situation. There won't be any new Acorn computer either, but there _has_ been new hardware designed to run RISC OS.
I guess what you mean is that there won't be any hardware designed to run AmigaOS? (yes, I've read the soapbox rant). Or simply perhaps no new computer called an Amiga.
I think the point is that RISC OS users are slightly more concerned with the OS itself (view the popularity of VirtualRPC) and Amiga users slightly more with the hardware it runs on. Although of cousre there are plenty of counter examples, and it's dangerous to make these kinds of generalisations.
I'm also willing to speculate that AmigaOS is a bit more portable when it
comes to new hardware than RISC OS, although that's perhaps an accident of history of 80s/90s hardware rather than anything planned.