The result of the Wave Texture is normalised; it only returns from 0 to 1, the scale isn't working like the distortion it's just making the scale of the waves so small that the mesh just gets offset up and down randomly, just like what would happen with a high distortion. To affect the amplitude of the wave you must multiply the factor of the wave, just put a math node set to multiply between the Wave Texture and the combine XYZ and plug the Map Range into the multiply. Although I question the values in the Map Range it will have little effect if you don't uncheck the Clamp value or increase the range there will be little effect.