Well, there is already hardware for AmigaOS that people can afford. That's what the entry level SAM systems are for. I suppose you could still critisise the SAM systems as being expensive if you're going to compare their performance/price ratio, but again that comes down to economies of scale and there's nothing we can do about that right now.
Yes, Sam440 is too expensive. It has been released 5 years later than Pegasos2 and is both slower and more expensive. We are talking in both cases (Peg2 and Sam440) about a small market so the low performance and the high price lacks any sense if you really want to make OS4 popular.
But, the fact remains, there are already affordable alternatives to run AmigaOS4 on if people prefer to go down that route.
I'm afraid there are not. Sam440 is not affordable. Moana would have been affordable but Hyperion decided to milk the users forcing them to buy überexpensive outdated hardware.
The X1000 isn't cheap because it's a high end system and, in small market like this, it's going to command high prices.
Our definition of "high-end" seems to differ. x1000 cpu is almost low end by today's standards. You can only find slower cpus in netbooks and even some of them now have dualcore Atoms (probably faster).
Still, even those prices aren't too bad when you consider what we're already putting up with on the second hand Amiga accelerator market.
Second hand Amiga accelerators are überexpensive collectors retro stuff, something that hardly looks reasonable once you use 5 minutes MorphOS/OS4 on a Mac Mini.
It's a pity they didn't publish Mac Mini version as they could have easily multiplied by 2 current OS4 base.
What AmigaOS4 needs is expanding its userbase to the maximum and x1000 won't achieve that. A powerbook G4 release would sell much more than any sam/x1000 version.
All in all: switching to 64bit will break binary compatibility, they could port it to x86 while they are doing that. If you sum the money invested in creating x1000, porting the OS to it and adding new features... you could do a x86-64 version using AROS drivers to save up developer time.