It may have been a mistake but it did add an important innovation: Postscript in the display system. This would be an innovation even now, having an interpreter for an embedded language right in the windowing system.
NeWS (developed at Sun) and Display Postscript (developed at NeXT) were each adaptations of Postscript to the screen. Apple (after the NeXT takeover) developed Quartz to avoid paying licensing fees to Adobe for Display Postscript. So yes, Quartz does something similar to NeWS.
- Adobe was uninterested in supporting Display PostScript by 1997. The cost was secondary.
- Quartz / Core Graphics is based on the PDF rendering model, which is derived from PostScript. You use C graphics routines to draw; there is no programming language.
Which brings us to the silliest part of the post: the idea that X won, or proved much of anything at all. X is basically noise in the computing world: the atrophied stump of the ix GUI market. The most popular Unix-like OS in the world is rooted in display PostScript. The most popular OS with a Linux kernel doesn't use X, or indeed a *ix-like userland.
