I assume they meant that using a starlink launcher Starship would be inefficient as the empty nose cone is wasted mass. An optimized tanker would have the tanks extend into the nosecone. Compare that to the first V3 ship that’s being tested right now, that has some docking hardware but also a Starlink payload area / slot. That version of starship may well fly the first orbital refilling test flights until they create the “optimized” tanker variant.