that's not freedom of speech.

Secret ballots are probably indispensible for democracy, but it is debatable (note I said "debatable") whether anonymity is necessary for freedom of speech and democracy. After all we've had many revolutions and regime changes in societies past where there was no anonymity of communication. Now arguably you could say that said regime changes might have occurred with less blood had anonymity been available, but then it is also arguable whether anonymous communication is anything like as forceful and persuasive as someone prepared to risk themselves by taking a public stance. IE we could argue that anonymous stances would not have created the regime change in the first place.

A whole bunch of avatars screaming a slogan is not persuasive.