I do speak my mind already,
And what you say is absolutely true — “disinformation” is whatever they say it is. But once you concede the government can go after you for nothing, why be anon? They could go after your real life identity for saying 2+2 =4.
And that’s what happened in Communist states in the past. Only a tiny minority of the 100M killed were actual dissidents. They killed people for any reason or no reason, in part because not enough objected when they had the chance.