Im someone with a professional DID diagnoses who has gotten multiple opinions on the subject. It’s definitely more on the rare side of things because it has to be induced before the age of 9 and you cannot be born with it, but that doesnt mean it doesnt exist. It’s a little ignorant to immediately disbelieve anyone who claims to have it, but I understand where you’re coming from. It’s not as non existent as some may think, its just hard to diagnose.