Apollo was building bit-slice 68000 emulations (to have an MMU) into the mid '80s, and ran Aegis, their homegrown fully-networked GUI OS, coded in their home-grown Pascal, with their home-grown touchpad pointer and home-grown token-ring network, on those and on actual 68K into the late '80s.
Aegis was inspired by MULTICS, not Unix, and was definitely a better system. They were demand-paging across the network in the early '80s.
One feature I recall stood out: they expanded environment variables in symbolic link text, like /usr/bin -> /usr/$SYSTEM/bin to get a SYSV or BSD Unix flavor, later on. The only Unix that does something similar I know of is Dragonfly.
Another was a read() system call that would copy into a caller-supplied buffer if it had to, but would normally just return a pointer into its buffer cache.
Aegis was inspired by MULTICS, not Unix, and was definitely a better system. They were demand-paging across the network in the early '80s.
One feature I recall stood out: they expanded environment variables in symbolic link text, like /usr/bin -> /usr/$SYSTEM/bin to get a SYSV or BSD Unix flavor, later on. The only Unix that does something similar I know of is Dragonfly.