There's absolutely nothing stopping a consortium of news outlets from adopting the W3C recommendation ActivityPub to push out microposts directly from their own content management systems, with an existing audience open web audience.
that centralization and processing of responses is by-and-large part of the social media problem (both generating the twitterstorm dynamic and having spawned the shadowy "sentiment" industry) but I suspect a lot of addicted users are quite keen to keep it going