After a controversial Tweet, for which he apologized, Glenn Reynolds explained here why he is leaving Twitter:

SO WHAT I’VE DONE WITH TWITTER is just to log out for now. The robo-tweets of InstaPundit content will continue, at least for a while. I may take down the widget on the sidebar, eventually. I haven’t moved to Gab, and I’m not sure whether I will or not. Basically, there are two problems with Twitter for me. One is that they don’t support their users — they pretty clearly suspend, ban, etc. using a political double standard even though they claim they don’t.
But the other problem with Twitter is that it’s the crystal meth of social media: Addictive, but unsatisfying. I’ve been spending a lot of time on it even though it doesn’t make me any money, and even though I kind of doubt it has much of an impact on anything. As I said a while back: “I think Twitter is overrated. It’s a good way to chatter with the chattering classes, but (1) it doesn’t drive traffic; (2) its impact outside the chattering classes is basically nil; and (3) it encourages people to think they’re being ‘activists’ when they’re really just tweeting to a few hundred people.”
That I’ve posted over 580,000 tweets in spite of saying that suggests to me that I’m not very good at following my own advice. Add to that the exposure to Justine-Sacco type shamestorms on a platform you don’t control, and I don’t see why I should keep working for them for free. And on that point, if I, a tenured professor whose university just admitted that his tweets are protected by the First Amendment, have concerns about this, I have to wonder why anyone whose job is less secure would stay on Twitter.

Of course, if you have a platform as popular as Glenn’s Instapundit you have options that others lack. Twitter and Facebook provides the other 99% with their own Instapundit-like platform. But, as others have noted, the thing about Twitter and Facebook is that they defeat the open access of the Internet itself, where anyone can post what they wish. Both platforms offer ease of posting, finding others, and reading along on cell phones in exchange for data collection and the controls of a gated private community, where there are rules. That may be perfectly fine, but when the regulated conduct in question is speech and the rules are enforced in a politically-biased and opaque fashion–as they have been on both platforms–then those whose speech is being (constitutionally) restricted need to consider their options, including denying such companies the revenue generated by their usage.

All of which is making me think I should blog more and Tweet less.