I think you're right. Plan9's first "public" (to universities only) release was 1992, when Linux was just getting off the ground and the FreeBSD & NetBSD projec

I think you're right. Plan9's first "public" (to universities only) release was 1992, when Linux was just getting off the ground and the FreeBSD & NetBSD projects did not yet exist. People interested in Linux or 386BSD at the time would have probably tried Plan9 if they could have.