I think they should have removed the dune and, in keeping with progressive management practice, planted more trees clear across to form a hedgerow but trimmed them up so you can see the landing area and the ball land on the other side.
Who needs a natural dune when you can add the artifice of a steeplechase? Resort guests could then look forward to playing the "signature" Steeplechase Hole and Hardelot could live up to its name.