Majority of (European) moderation in Twitter is done in Russia, or Russians residing in Malta or some such place. I used to burn Twitter accounts by the dozens by trolling^H^H^Hdiscussing issues that only Russians have opposing and sentimental view -- like Winter War, or origin of "Rus", or Crimea occupation.
In 2016 there were Russian accounts with hundreds of thousands of followers. They maintained accounts on both sides of contentious issues and pushed inflammatory stories simply to increase divisiveness.
Stories they wanted to promote, whether they created it or not, they could use bots to push to higher visibility. It isn't as if any one vote made the difference.
If you desperately wanted to know what American "Alt-right" was thinking 2016, you subscribed to Milo Yliannospullo, Gavin MacInnes or Steven Crowder, but they are all banned everywhere now, and they are not Russians.
You misunderstand the situation. They weren't posing as Russians. They were posing as Americans as individuals, as news outlets, as political organizations:
https://www.nbcnews.com/politics/national-security/russian-t...
Quoting a bit from this:
They posed as local news outlets, such as "New Orleans Online," "El Paso Top News," and "San Jose Daily." The majority of these accounts were created between May and August of 2014, but lay dormant until January 2015, when most of them started tweeting. This suggests a significant element of advance planning, Symantec said.
- newly created account (or, in the more sophisticated variants, an account created some time ago with a few meaningless postings) - ask for help, or ask a question to distract from the actual goal - somewhere in the text, throw in some association that should stick (like "refugees steal", or "refugees sexually assault woman", as a fact that doesn't need discussion) - when confronted, the only answers were contentless excuses, like "but I am really asking this for my mother, who can't use a computer". Never any attempt to engage in actual discussion.
The reaction to these is that people usually address the question, don't address the baseless association, which probably then starts to stick in the unconsciousness of at least some of them.
And on the political side, at the same time there was an increase in support for extremist and nationalist, anti-foreigner parties.
Though of course how much such messages contribute to that is difficult to say.
https://gru.gq/2019/12/07/baltic-counter-disinformation-2/
This explains more background:
https://gru.gq/2018/11/08/russian-propaganda-isnt-even-good/
https://cdn.cnn.com/cnn/2019/images/04/18/mueller-report-sea...