I like much of the advice, but the style and presentation of the message is, like so many things I've seen associated with Facebook, lacking any sense of humility. There's no "we did this because it worked for us and we're sharing in hopes that it may help others." Instead it's "Other people think this. They are wrong." Or "A commonly held belief is X. It is false."
This hubris has certainly been a powerful ally to Facebook's founder, but like so many other powerful people, companies, governments and organizations that came before them, I can't help but think it will ultimately lead to demise (unless tempered).
While hubris can be a problem, I'm very much a fan of stating your opinion clear and bold. One might be wrong, but astute readers should be able to judge ideas for themselves. Speaking clearly will also make it much easier for people to see if you're wrong.
I think giving clear statements of your opinion and being proven wrong is much better than obscuring your point with "maybe" and "personally" and "IMHO". That's depending on the context of course, as you don't want to unnecessarily offend people (which is bad in general, but also counterproductive). But in a general analysis like this, not attacking particular people's shortcomings? Go for it.
A reminder to "think for yourself" can be helpful, and does not necessarily imply a lack of clarity or boldness. Sometimes a story is told so well, that you get emotionally wrapped up and forget to take a step back and make a fair-minded analysis. Not everyone is an astute reader.
You also included some conditional statements with, "depending on the context" and "But in a general analysis". I see no problem with acknowledging that things aren't always black & white.
I have to single this out: must we all prepare our rhetoric for the remedial education of those who were never made self-sufficient in the processing of external knowledge into internal beliefs?
This hubris has certainly been a powerful ally to Facebook's founder, but like so many other powerful people, companies, governments and organizations that came before them, I can't help but think it will ultimately lead to demise (unless tempered).