Implement ActivityPub (an existing protocol recommended by the W3C), and offer their underlying social networking services as hosted and managed software for big orgs to operate on their own domain. With interoperability, they'll work across domains. Target customer is anyone with at least 100K followers (so gov, institutions, media, et cetera).
Hey, if they get that implemented for Facebook, maybe they can try to make it work with health care records too. Good luck with that...