Hmm... RISC OS is a development of Xara's original platform, and it's a RISC (obviously) processor (XScale, which is a development of the ARM, and now owned by Intel). Yes, Acorn died, but RISC OS persists, stubbornly refusing to go.

Of course, I can understand that Xara may not want to put any resources into porting for what must be a mere sliver of the potential market, but would they be willing to allow others within the RISC OS community to do it?