To me, Twitter is a guy in a crowd saying something. There will be followers nearby who presumably like what he says (or why are they there?). Then there are others away from the followers who overhear the (potential crap) he says. They respond. Or not. It is like being in a crowded bar and walking past discussions: just snippets of text with zero context (by and large). It is "communication" for people without RL friends or who have zero interest in responses to their statements. It is the ultimate self-validation: you actually don't care about dialog, just monologue.