I've highlighted this before and will highlight again. Removing the old displacement was a terrible move. It fixed a lot of problems with displacement that are evidently still there, like the one highlighted in this thread. Subdivision is not the answer. It's ugly, messy and adds uneccessary geometry to heavy scenes. It looks horrendous on clay wire renders too, and they're used all the time for previz in a lot of arch Viz workflows. Currently displacement only works on ultra clean meshes, terribly subdivided meshes, or meshes so dense that you can't see the problem. Its madness to me that the old method was removed - because it worked. Simple as that. Now it's gone, you can't fix these current issues without workarounds. That's a step backwards, not forwards