Marc, you are right, but the OpenLook/Motif stuff was >>much<< later. Matt asked about the SVID thing about 5-6 years before that.
The problem AT&T had was >>before<< Judge Green, they could not be in the computer biz, so they "abandoned the sources on your doorstep, with no warranty of any kind." It was simply thatAT&T was not allowed to be in the computer business by law. Post Judge Green boy did AT&T's management >>want<< to be in the computer biz, and they tried to use tactics that had often worked for the largest computer firm to date. In fact, the firm that Charlie Brown [the AT&T CEO] was quoted as saying, he wanted to compete with and emulate IBM. If I recall correctly, he said something about matching them move for move. UNIX had been AT&T's baby, and AT&T wanted it back, but by then, the child had grown up and did not want or need its parent anymore. A lot of the failed actions post Judge Green are part of AT&T searching for a grip in a business its management team did not understand, nor was prepared to be a part of.
The assumption was that before the breakup, they were the world's largest company, and even after, the new AT&T was still larger in assets than IBM, so they could compete. History proved otherwise. If they had used different tactics, with the assets AT&T had in its quiver, they might have been able to be a real force. But I think pride made them think that the 3B20 was going to be able to compete with a Mainframe (or even a Vax) — mind you, their own people wanted Vaxen or later Suns. AT&T Management seem to think that UNIX was the key, but AT&T had to be in charge of it. The funny thing, is if AT&T management had taken a zen approach and bolstered what everyone else was doing instead of trying to drive everyone else away [Microsoft's famous "embrace and extend model"], and not tried compete in the processor wars, but instead take on second source licenses and start using their boundary; I something wonder if it might have had a very different out come. They still would have needed to see the PC revolution coming, which I'm not sure management types used to 40-50% gross margin will ever under as 12-15% margin PC market (volume is everything) market.