Have Twitter (and Facebook) provided valuable information to the world? Sure. Have they also harmed democracies? I think it's fairly obvious they have.
Oh shoot, turns out it's a complex issue...
This is why intention is so important when interacting with new technologies.
It's all in how you use it. I honestly think Twitter is the only decent one out of all the big social media sites. They give you really good filtering capabilities, the ability to hide sponsored posts, and the content is actually accessible via the web, not locked within their walled garden a la Facebook. Twitter is great if you curate the people you follow and stick to technical and scientific topics. Avoiding politics is the key; 140 characters is simply not the platform to have those kind of discussions, which leads to the toxicity.
By the way, the character limit has been doubled to 280 a few years ago.
Well, look at Twitter now. I got what I wanted, and I hate it. I was wrong. I’d happily go back to early Twitter.
It seems that Twitter makes it much easier to follow and hear from US representatives.
Twitter can be useful for following people and orgs you care about. And TBH, the "hot takes" I have sometimes seen on Twitter have changed my opinions about things. And people are using it now, in America, to share videos and communicate about things like they did in Iran 11 years ago.
Where Twitter fails to be useful is in
* Trusting it too much when you don't already know the source
* Looking at the replies to Tweets (IOW, tweet convos are rarely useful)
* Hashtags as journalism (#blah is trending!)
100% of Twitter’s value is network effects. People are there because other people are there.
So even though people like Trump are technically a nuisance for Twitter, they are also the reason why Twitter has millions of people on it.