Being able to speak freely is utterly pointless if no one else is allowed to listen. I am positing that it is immoral to legally limit the consumption of political speech by any person.

At no age is it currently illegal to own a violent game or R rated film. Film ratings are enforced voluntarily by private actors and not by the force of the law.

There is no reason for that to change for any medium without extremely strong reasons considering the free speech implications of giving the might of law to arbitrarily restrict content at their individual whim. It seems to me there are not even weak reasons currently, only absurd reactionary politics that always follow tragedy.