Yeah get a mac and get an OS from the 70s
Which was designed from the get-go for multiple hostile users, not one friendly user.
The historic roots and the “grand architecture” ideas behind VMS are also from the 70’s. Much of the IO device architecture of VMS (and now Windows) actually goes back to RSX-11, not VMS.
Windows NT is based on VMS, from the 70s, the API having its origins in 16-bit Windows from the 80s. OS X is based on FreeBSD from the 90s, which is based on 386BSD from the 90s, based on BSD, and then UNIX from the 70s. But that's on one lineage for the user space, file system and network. The kernel is MIT Mach from the 80s, and the API and other technologies are from NeXT in the 80s.