I am completely behind thinking a DM banning races in their game that they do not like is a valid call.
If for example a DM likes a lot of
Dragonlance, say for the dragons, the knights, the wizard orders, the elven and dwarven politics, the draconians, the minotaurs as a race, and the gods, but dislikes the Kender, the Tinker Gnomes, and the Gully Dwarves I think it is fine for them to choose to offer to run a Dragonlance game with no really small folk.
It would be the same with Star Wars and ewoks or Cyberpunk and netrunning.