IIRC, it was the case that for commercial Unixen, the Single Unix Specification v.2 stated that amongst other things, the vi editor always had to be available.
So, vi gets dragged in as part of your vendor's commitment to "standards compliance". Also, for SUS purposes, vi means SysV vi, not vim. A far less domesticated creature.
In a base install of Solaris, Irix, HP-UX or Tru64, it'd be the only editor you get. Vim, emacs, nano, joe etc. would all be in a seperate "freeware tools" or somesuch sideloaded optional install set.
Not only that, but vendors would freeze those tools in time.
I worked for an employer who banned "freeware" tools so you were stuck with ancient, broken software on Solaris and other systems.
Post 9-11, we had to secure all of the things, including moving away from rsh and telnet. SSH was problematic due to the freeware thing -- no worry... we were able to buy "IBM SSH" for $900 per processor value unit. (IBM SSH was an out of date OpenSSH where someone did a find and replace substituting Open with IBM)
So, vi gets dragged in as part of your vendor's commitment to "standards compliance". Also, for SUS purposes, vi means SysV vi, not vim. A far less domesticated creature.
In a base install of Solaris, Irix, HP-UX or Tru64, it'd be the only editor you get. Vim, emacs, nano, joe etc. would all be in a seperate "freeware tools" or somesuch sideloaded optional install set.