My point isn't that meaningful conversation is impossible on twitter. Its that the majority isn't and most abuse the gift of an instant global platform. Its tragedy of the commons on an unprecedented scale.
Of course there are worthwhile interactions to be made. But the people making them would have been doing so on the less accessible older internet anyways.
These things existed, but you usually had to go seek them out specifically. You weren't reading a friend's, say, blog, when suddenly a link to some exciting online argument about some nonsense appeared. That does happen on ~all social media. Unfortunately, many news(paper) websites are baiting with "hot" controversial topics now as well.
Of course there are worthwhile interactions to be made. But the people making them would have been doing so on the less accessible older internet anyways.