Re: To some MSDOS was an major leap forward.
Back in the day UNIX was 16 bit.
More than likely because most Z80 machines back in the day only had enough memory for a UNIX kernel and not much else.
A Spectrum 128K/+3 or Amstrad CPC 6128 could just about manage it, if you could live without memory management. A 6502 machine like a BBC even with extra memory probably couldn't because its stack has a maximum length and is stuck at the bottom of the memory.