I use Twitter, usually, for about 15 minutes every morning to collect links of stuff that I should look at when I have time. I am taking a RL and thought about following the two excellent professors teaching the class. Neither was on Twitter, which makes sense: they probably don’t have the time to spend/waste.
To me, this article itself exemplifies one of the problems I see with social media, which is that it seems to instill in its users the feeling that they need to "PR" their online presence, writing articles and explanations for what would otherwise just be simple, noiseless decisions. IMO if you want to leave an online community, just leave- there's no need to put out a press release on your way out the door.
I notice that the more someone is active on Twitter (especially politically), the more toxic they are. They tend to carry that whole Twitter etiquette with them everywhere, be it on Slack in the workplace or in the office for example. I wonder if Twitter, the way it works specifically and the incentives it gives to users, has a net negative effect on its users' wellbeing in general.
It's hard to imagine a more toxic mainstream platform (by "mainstream" I am excluding the likes of 4chan and certain Reddit subs). I can't really think how I would design a system to better promote ad hominem attacks and mob mentality over thoughtful discussion.