Lol
If you didn't give a shit about Mihawk having it before, don't get indignant about it now. Zoro is Zoro. That has nothing to do with Mihawk, Kuina, Helmeppo, or Tashigi etc.
Does Mihawk need it? No. Oda has not confirmed Blackbeard, Mihawk, or Sakazuki, but went out of his way to confirm Sengoku apparently. That doesn't actually determine relevance to the story any more than being a D does.