Isn't there a third vector at play here?
I like this article insofar that it indeed highlights some fallacies and highlights the age of consensus as behavioural model (a model which makes me glad people like Jack Nicholson exist, grin).
There is, however, a third vector at play (IMHO): this assumption that it is actually good to share and the unrelenting pressure to do so. We are absolutely BURIED under "share" options. Worse, it's even integrated into operating systems so you have to be very careful that you don't share by accident, and by that I mean publicly, not with the NSA..
I have, as yet, to discover an instance where sharing is indeed recommended. Twitter? No, thanks. Facebook? Nah. It may have to do with profession: by their very nature, the companies that make their income by creating an online "presence" like marketing and PR outfits may indeed seek to live online, but for instance lawyers, advisors and doctors are as absent as they should be. Anyone tweeting "RIP appendix LOL" should be struck off, but you thankfully need a brain to legally approach an anaesthetised body with anything sharper than a penknife (and my hat off to you all).
I've tried the Facebook thing - it doesn't work for me. First of all, I am aware of how fickle public life is (just be a named knowledgeable commentard here and see how many people seem to have a need to spout opinion based on nothing more than an at best passing acquaintance with the topic at hand and magnify that x100 to get an idea of the unspecialised version of online life), secondly, I take the Groucho Marx approach to groups (not interested in any club who accepts me as a member :) ), and thirdly, as I am well aware of gaming theory I didn't do the "friends" numbers thing. If it floats your boat, be my guest. Just don't bother ME with it, or worse, try to impress me with it.