This is more than likely a translation error. Once Again, ERA jumps to conclusions because they can't actually read the interview in context. This reads like they can't just slap a new hairstyle on a Toad and call it a day like the past games. They need to create original designs and characters that aren't based on any existing Mario character. So no, Nintendo isn't forbidding them from making original characters at all dumbasses, the team is just no longer able to drastically alter established designs like they used to.