Totalitarian governments traditionally generate fake news to help cement their hold over people.
Remember the Iraqi Baathist party official (can't remember his name) who held press conferences detailing the great victories of the Iraqi Army over the U.S. right up until the U.S. forces took control of Bagdad?
Remember Stalin's efforts to edit people out of old photos?
Remember Hitler's many stories of Jewish atrocities, Blood Libel and all that.
Fake news has always been a tool of oppression, and I am supportive of any effort to verify news and to debunk and expose that which is false.
Having said that... fake news is different than propaganda in the sense that fake news is not necessarily partisan. A lot of it is strictly commercially driven or even just hoaxes for entertainment's sake.
An example of the former, going back a couple generations, is Bat Boy.
An example of the latter, going back a couple more generations, is the anonymous amateur radio operators who broadcast that the Titanic was not really sinking, so no need to send rescue, everybody turn back. 1912's version of trolls.
The third type, which you have examples of, is propaganda. It's designed to convince the public to support one party over another, but is dependent on people paying attention to media.
The new type is sort of flooding, with the intent of destroying the concept of reliable news entirely. This is a post-propaganda strategy. As I mentioned, I have a lot of relatives who used to live behind the Iron Curtain. For example, East German relatives, who knew three things: 1. the government controls the media, so it's all lies. 2. some of your friends are paid to inform on you, so don't talk politics. 3. the only things you know about politics are what happened directly in front of you.
Flooding with fake news doesn't explicitly help any particular party, but it does help totalitarian leaning politicians regardless of party because it corrupts the marketplace of ideas. This is why it's a threat to democracy.