First of all, retaliation clearly has its place. If someone acts in a way that wantonly hurts others, it is the correct choice to inflict some suffering on them, for the sake of setting the right incentives. It is indeed extremely common that from this perspective of fairness and incentives, people “deserve” to suffer.
I don’t see why it’s good to punish people. If you threaten to punish me if I do a particular thing, I’ll just get upset that you might hurt me and likely refuse to interact with you at all. But you do sometimes have to hurt someone’s reputation as a side effect of some other necessary action, like warning other people that they’re untrustworthy.
I don’t know the details of this whole nightmare, but I’d hesitantly suggest that free speech helps people find the truth. If someone is wrong about something, talking to her might help her figure out she’s wrong. If she’s egregiously wrong about something with enormous stakes, then that only increases the importance of talking to her.