Well, it's a subject I find interesting but I can't claim to have any expertise so anything I say is best treated as half-baked speculation, but I know there's more to it than postcode alone, and there could be all sorts of reasons why it is a mere Bordeaux Superieur rather than a Haut-Médoc or Margaux.
But does it matter anyway? It doesn't surprise me at all that a bunch of upstarts who have only been in the business for 30 years, probably with progressive ideas about viticulture, would find it hard to get recognition from the Bordeaux wine establishment. Very much a closed shop. So much snobbery and politics involved. If it's good drinking, that's all that really matters.