Like the part about the birthdate is supposed to be humor maybe? But Google already knows how old you are.
That's why I think it's funny that they claim they will now be "using AI" to determine if someone is an adult and able to watch certain youtube videos. Google already knows how old you are. It doesn't need a new technique to figure out that you're 11 years old or 39 years old. They're literally just pretending to not know this information.