Making the GPL more scary

At heart, it was a legal reflection of a complete breakdown of collegial relations between an old guard who had commit access (including several, like Wexelblat, who had gone over to Windows and hadn't worked on the project in many years) and the "punks" who wanted to bring X, insomuch as it was possible to do so while maintaining wire protocol compatibility, into the modern world.

Since the punks were doing the work and had backing from the distributions, the fork had a fairly preordained outcome, which can't usually be said about forks. And the rapid pace of development after the damage was routed around speaks for itself. In particular, the release of a modular X11 with a mainstream build system was achieved in relatively short order, an enormous step forward.

(When was the last time anyone ran "xmkmf"?)