I could really use a "special edition" of MacOS - sort of like what happened with XP in the later days. Strip out all the Apple stuff, privacy failures, and excessive gatekeeping [$] and just leave the raw OS.
What UNIX are you thinking of? Even the Berkeley distribution appeared to require a license from AT&T to use, for V7 UNIX. Anything with AT&T's code was litigiously protected, culminating in a law suit in the 90s against 4.4BSD Lite, which was the first to claim to be rid of all AT&T code. Are you saying most installations were just unlicensed copies?
[$] for me