> it's no more the ancestor to my phone than an Apple II.

It really is.

Both Acorn (BBC Micro designers/manufacturers) and Apple Computer (Apple II ditto) bought in the MOS 6502 chip.

When it came to successor models, both tried the 65C816.

Acorn made the Communicator:

https://chrisacorns.computinghistory.org.uk/Computers/Commun...

Apple made the Apple IIgs:

https://americanhistory.si.edu/collections/object/nmah_55324...

Both were not delighted with its performance and looked elsewhere.

Apple went for the 68000 for its next mass-market model, the Mac. (I am aware the timeline is more complex; this is a simplification.)

Acorn evaluated the 68000, the 80186, the NatSemi 16032 and others.

It designed its own chip instead: the ARM, Acorn RISC Machine.

This was first launched as an add-on accelerator for the BBC Micro.

https://www.computinghistory.org.uk/det/48862/Acorn-1MB-A-Se...

It was later launched as an Acorn computer, running a 32-bit port of Acorn's MOS and BASIC. It included a 6502 emulators and so could run some BBC Micro software.

https://www.onirom.fr/wiki/blog/21-04-2022_Acorn-Archimedes/

That ARM chip is the direct ancestor of the chip in all Android devices, all iOS devices, and modern Macs.