That is, if they are prey. Ponies, while sometimes intimidated by their size, don't act like prey in the presence of dragons and dragons never show any interest in eating them. Ponies also say outright offensive things about other creatures all the time that have nothing to do with any predator-prey relationships, dragons included. So giving ponies that defense and putting that defense next to their behavior, it easily stands out as a Neighsay-tier excuse to just be jingoistic bigots.