Firstly, "free as in free-speech" isn't codified anywhere. Nominally, and jurisdictionally, US constitutional First Amendment rights would apply, since the BV Discourse server is hosted in Ann Arbor, MI, but you have to be aware that the First Amendment doesn't give freedom to say whatever you want, whenever you want, to whomever you want. The First Amendment simply guarantees that the US Congress will not pass legislation which denies freedom of expression:
What the First Amendment does not do, and additionally what the UNHCR and EHCR instruments also do not do, is guarantee your freedom of expression on a privately owned, privately funded website.
Granted, there is no explicit curbing of speech codified anywhere on the BV forums, however, the code of conduct here is don't be a dick. We've had one ban already due to extended dickish behaviour, and while I'm not saying what you said was something that would merit a ban (not that I could extend the banhammer, even if I wanted to), what I am saying is that -- in my humble opinion -- what you said and the way you said it was approaching microlevels of dickishness. Nothing inherently awful, or disrespectful to any individuals here, but towards the level of "dude, come on, this isn't 1995, we've all grown up a bit".
I know a lot of people who work, and have worked, at varying heights of position at Facebook. Not just "oh yeah, I've heard of them and poked them once or twice", but friends I know personally, some of them really good friends, a lot of whom I've worked with before. They've worked at levels from engineers all the way up to VP. They're good people. They have good intentions. They're not sitting around wringing their hands together, twiddling moustaches, and plotting on how to ... well, be dicks.
And finally, as I, as I've said previously: