Earlier quoted context omitted.
With Mark, saying and doing are two completely different things. Example: "Helping poor people in third world countries get online" turned out to be: "Deceiving poor people in third world countries into using something called 'Internet' that's actually 'Facebook with apps', and depriving them of real online access." That whole thing ended up being an attack on the free and open web. "Share with friends only" is short…
The last time I checked, using Facebook was entirely voluntary. The existence of it takes away nothing. You have everything you had before, and also the option to use Facebook or not. There's nothing disempowering about that.
It's not inconceivable that at some point some country (perhaps very close to home) might decide that having a Facebook profile is mandatory in order to operate a business. With their Real Name™ policy it might even be useful for registering citizens. You can see this already happening on a smaller scale with some companies requiring Facebook login in order to use their product or service. I see others calling Facebook a "public utility", seemingly unconscious of where that road leads.
Sure, you can say all of that is still "voluntary". You don't need to use that product and you don't need to even be a citizen of the United States. You could move to some part of Africa where Facebook has not yet commandeered the social infrastructure. But, somewhere around that point I think most would agree that the word "voluntary" ceases to have any real meaning.