I suspect these 'misinformation campaigns' are completely ineffectual and the main effect we are seeing is factual information routing around mainstream media outlets and successfully embarrassing subjects that the mainstream media would rather protect.

For instance it was very embarrassing for the mainstream media and the democratic party that leaked emails showed them in collusion and undermining Bernie Sanders, but this was not misinformation. Likewise it was very embarrassing for the foreign policy establishment when their tools such as the oscar-winning White Helmets relief-workers were photographed arm-in-arm with rebel militants and shown staging videos, but I didn't see any of this exposed as 'misinformation.' I guess it was just 'the wrong information' to be reporting on.

Revelations like this are much more powerful than silly memes from Twitter accounts with no real followers.