I think the best solution is to ignore this and quietly add it to the blacklist. Such people provoke reactions, and if there is always emptiness in response, then they will not get what they want. After a while they will stop doing it. And what happened now they got what they wanted unfortunately. It's not easy, but it's the only way as I see it. Decentralization makes it more obvious, shows that there are such people, but we get an open and transparent picture of what is happening and together we can cope. It is much worse when such people are at the head of centralization and this is really a disaster.