I don't personally have any phobias, and I still think phobia modes would be a very good accessibility feature. I have a friend whose phobic of centipedes, and he really can't help it, but he loves everything else about the game including the horror / atmospheric aspects. I don't think letting people like that turn off or change how the creepy giant big looks will ruin the game's atmosphere, if you ask me, especially if it's incredibly optional.