The Natural Philosopher wrote:

Apple went for the 6502 IIRC

Yes, first three machines I used were all 6502 (PET, UK101, BBC) then I
moved onto Z80 with CP/M, OS/M and MP/M

I don't think many people used 6809, although it had a simple clean
instruction set

later I used 6809 with OS-9 and found it was like coming home to a
grown-up 6502.