I searched for "ARM" and didn't see it in the article. The Acorn ran on ARM (that's what the A in ARM stood for anyway, Acorn RISC Machine)
You can run RISC OS on a Raspberry Pi which is also ARM based.
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You can run RISC OS on a Raspberry Pi which is also ARM based.
https://www.theregister.com/2025/04/01/risc_os_open_moonshot...
... And I'm still talking with ROOL about the directions they're examining. The restriction may no longer hold true.