But Mastodon is not the only way to manage accounts and publish stuff. It has so much overhead because it has to look and behave like a Twitter clone, whereas you could simply have a barebones password protected web admin panel to allow each journalist to publish with their BBC-approved credentials.
With an entire Mastodon installation, then each journalist can also keep up with and talk to sources via a Twitter-like interface. Though they will quickly want to move any serious conversations with information sources elsewhere what with the big undismissable "hey this is NOT REALLY PRIVATE" sign at the top of the "private" messages column.
Also I suspect that "what if we just set up a Masto and see how it goes" might be a much smaller investment then "add AP to our CMS". They're only committing to six months of this right now.
I'm unsure how much overhead there is since the service discussed above is functionally a micro-blogging service. Also I think you're missing on the important feature of having an easily recognized format (even if it is a clone)
