A/UX was released for the Mac II in 1988, then in 1993 Apple changed course with a series of servers, before Mac OS X Server in 1999 and its first Xserves in 2002.
Macintosh II
What is a similar size and weight to an iPad Pro, runs for a similar time on battery, but was launched in 1987? The first proper laptop.
Whilst not exactly a lemon, it was not the flagship product which it could have become, and only made it to version 3.
The Eclectic Light Company 