It seems Stern (in various guises - old Stern, DE) were never innovators, just imitators. And with nothing left to copy, they have no direction. Stern copied the Bally board set originally, then copied the Williams System 11 for DE. I can't think of a game in any of their incarnations where they came up with something truly new.
Perhaps with nothing to copy, they are struggling with direction?
GS has said recently that there is not room for two pinball companies in the world now, and another company would likely see Stern fail. Sounds to me like a guy in fear. Maybe they do need another pinball manufacturer, so they can copy their inventions!!
Feel free to debate.