If you want to predict the future just look at history. The belief that somehow these groups will get it right and aren't inherently harmful is false.

At my prior job we were fairly big (1000+) and had internal meetings more or less instructing people how to vote. We had a significant social reach and the ability to promote arbitrary articles such as news. We had editorial guidelines forcing us to be politically biased. As much as I disagree with the current president I do think there was some sort of attempt at manipulation. Whether it was successful or not is beyond my ability to analyze.