Well, thirteen is the age, you know, puberty happens. You become a teen at 13, and there's a LOT of inappropriate stuff out there. You usually get, "The talk" once you've become a teen, and thus all the inappropriate stuff won't confuse you, and you won't grow up to be a very vulgar person. Besides, thirteen is a pretty kind and considerate age to be able to go on certain apps as parents will still treat you as a child at 13, and only really get treated as someone mature when you're 16. If media apps were like parents, you would only be able to create an account at 16, so yeah, be grateful you only have 1-5 years to create an account. This coming from a 13 year old, mind you.