If his cited sources (which presumptively were somewhat important to the point he was making) should (or would have, which may be subjective. I don't know because I'm not a Facebook employee and have no direct knowledge of the now-secret information) have been secret, then it stands to reason that it would have been more difficult for him to make his point.
If that's the case, it sounds like they've changed an entire policy organization-wide to stop more posts like this, or they've made no global policy changes and selectively hidden information that would support his point. Either way I'm curious about this culture of openness and what defines its limits.
But that content is not typically hidden at Facebook? And it's hidden now, precisely when it would provide evidence as to whether or not the alleged executive conduct happened? And you... have no opinion about that? Really?
How confident are you that you know how things work "at nearly any other company?" Is this something that someone told you, or do you have some way of knowing this yourself?
I have no opinion about why content was hidden. At nearly any other company the same content would have always been secret.