We know that this already happens, but now its in the grasp of many people and thus much harder to pin down where its coming from and what that party's motive is. How can you 'follow the money' when - it requires almost no money to spam every social media channel - then get picked up by news bc they turn to social media for fast/new/relevant information
But we have been here before. When radio first came out, it had an almost magical sway on people. People attribute the newness of radio as a significant factor in hitler's rise to power. Eventually we adapted to it though, and it lost its magic sway.
I interpret your opening statement here positively. I tend to think most people work towards the good of mankind, so a boost in productivity for everyone is a net positive.
It may be in your nature to question everything you see, hear or read. I'm pretty sure that's not the case for the vast majority of population. And as magical ChatGPT seems to all the tech and non-tech people, it is really difficult to predict what it will look like in 30 years from now. It may now take 100 trolls to spread fake news about Ukraine on Twitter.
In 5 years from now it might take one prompt and you will be able to cover every single social media on the planet in convicing information from many spectrums of the opinions. What you might see could be 10 people violently arguing on the internet, whilst its all bots whose only purpose is incite emotions and polarize people.