The Efex plugins are the only ones which offer better results than the comparable features in PhotoLab so in this case DxO made the right decision here on which plugins to prioritise.
Most of the people using the Nik versions of Viveza, Dfine, or Sharpener Pro probably don’t have 4K monitors and may have been used to running Nik plugins without PhotoLab. You now have PhotoLab built-in to Nik gentlemen so there’s an easier and better way to sharpen and use U-point technology on your images.