imho (and I wasn't there at the time) this is a result of proprietary unices constricting the growth of 'free unix' (e.g. source based BSD) in the commercial re

imho (and I wasn't there at the time) this is a result of proprietary unices constricting the growth of 'free unix' (e.g. source based BSD) in the commercial realm along with the rapid growth of space-constrained 90s PC's and "unix" users who came up in this commercial "unix" environment.. linux distributions were designed around the model of binary-only proprietary "unix" that just happened to have also have source available as a bonus instead of comprising a fully self-hosting source+binaries+documentation system like research unix and source-available derivatives/patchsets (like bsd, etc) always were from day 1 My personal opinion is that unix is a culture and not a trademark, the culture is the users and systems based around this self-hosting system with source lineage back to the original. Binary unix-derived distributions (and unix clones like linux) are therefore implicitly not unix since they are not out of the box self hosting and source included to one degree or another, and do not have a direct code lineage back to at&t v7. At best, they are some approximation of 'unix like', which can still of course be pretty useful.