When using a procedural map as a displacement mapit seems to tile the “first” appearance of the map rather than uniquely changing over the course of the entire UV, as it would if I had it as the diffuse texture or even bump map.
Can displacement modifiers utilize procedural maps?
Have you changed Displacement Mode to 2D Displacement in this case?
If yes, please note that this method cannot be used for 3D procedural textures or other textures that use object or world coordinates.
With Normal Displacement and your Noise settings it should look like this:
