Will Genesis ever take V3 (Gen 3) textures, MATs, skins, etc?
I doubt it. Most of those textures won’t look very good in either current versions of DS or Poser. Lighting in both programs has gotten much more accurate since the V3 timeframe. A lot of them had effects burned into the jpg to make up for deficiencies in the lighting system.
If there are V3 skins you want to use, your best bet will be Texture Converter.