For sure I'm on the same page as you that the current "media climate" is not necessarily a healthy one for society as a whole. But almost nobody uses that kind of "if everybody simultaneously stopped doing X the world would be a better place, so I'll stop doing X" mentality when deciding on their own behavior. Hence climate change, nuclear de-armament, etc.

The arguments on HN and other places for "online privacy" aren't usually hinging on this tragedy-of-the-commons point. They're usually heavily implying that some very real and personal harm is being perpetrated on the unsuspecting sheeple right now and if only they understood what was really happening they'd be up in arms. I don't think a vague uneasiness with consumerism in general is what they're alluding to.