If anyone here could be reasonably construed as arguing from ignorance it'd be you.

You said that "there are many much more subtle and effective ways to stifle free speech and human rights than a big firewall," such as "MITM attacks, botnet troll armies, astroturfing, etc. etc."

If you're not asserting that such techniques are being deployed, then ok. But if you are, and follow that up with "Good luck finding proof of that though," as though that's a perfectly reasonable excuse for not being able to back up what you're alleging, then you are yourself asserting "a proposition is true because it has not yet been proven false."