Right, it's not immediately about copyright, per se. But the GPL relies entirely on copyright and if this ends up setting a precedent that you can't use copyright to enforce the (unfortunately vague?) terms of the GPL, that weakens copyright.
It's a good question if it does "weaken copyright". That would be a good thing, and a primer in thirty+ years, because it would equally reduce its breadth from proprietary applications.
By what I see now (from old and new, but cursory public information), most likely, VMWare has too big resources for a long protracted legal battle, and I don't know if Conservancy can stand to it. That's not the same thing at all.
