Nebulous allusions to evidence gathered about a hypothetical mass media system that we don't actually have aren't equivalent to actually providing that sort of evidence. I'm perfectly willing to go out on a limb and say you don't have any such evidence and that until you do, you haven't actually provided any reason for anyone to believe your claims about harm. Moreover, given that you're not obligated to consume media (unlike say, medicine or food) the harm is that of someone deliberately walking into someone else's outstretched fist. You'd also have to show that the harm isn't self-inflicted (which is completely impossible).