Indeed, and Divx was actually a commercial failure, partially due to how annoyingly complex their rights management was (but mainly because their partner was dying).
DRM (and similar tech) works pretty well in specific cases, like printer-ink DRM. I actually think ERM was a great idea, but sadly failed to DLP and other solutions (basically blacklist vs. whitelist of permitted activities).
Where it fails is software, particularly "media content", on commodity players, fully in possession long-term of end users, who are otherwise hostile, with no real costs to a failed break attempt.
The printer ink thing is probably their #1 success story, although the non-DRM version is to build some patented shape and rely on patents for protection, which may also work. (IANAL though; I know you can do compatible designs in some cases, too).
This whole "DRM for 3d printing" thing is a red herring -- the real war was "DRM embedded in physical devices we purchase", like auto parts and ink, and that was fought and lost in the last decade.
DRM (and similar tech) works pretty well in specific cases, like printer-ink DRM. I actually think ERM was a great idea, but sadly failed to DLP and other solutions (basically blacklist vs. whitelist of permitted activities).
Where it fails is software, particularly "media content", on commodity players, fully in possession long-term of end users, who are otherwise hostile, with no real costs to a failed break attempt.