I often feel like sentiment such as this assumes that these kinds of notices, movie ratings, "clean" / radio versions of media, etc are solely meant for teenagers.
Maybe that's how they relate to it - as some kind of restriction as a teen.
Keep in mind that while you will learn this stuff in your life, for very young children, there is definitely a lot that is inappropriate whether it is sex, language or violence. A 2 year old is unable to fully understand what is appropriate when. They are not ready to handle many of these concepts.
Beyond that, if an adult doesn't want to listen to something or watch something, this helps them. If they've don't want to see or hear something, why should anyone else care?
Keep in mind that while you will learn this stuff in your life, for very young children, there is definitely a lot that is inappropriate whether it is sex, language or violence. A 2 year old is unable to fully understand what is appropriate when. They are not ready to handle many of these concepts.
Beyond that, if an adult doesn't want to listen to something or watch something, this helps them. If they've don't want to see or hear something, why should anyone else care?