How would email and RSS be the next big thing? Because that is what https://atproto.com/ is, and to some extent, here. A private entity or individual cannot capture the AT Protocol network as happened to Twitter/X, it has already succeeded.
Certainly, this is a different perspective than "What metrics can we use to value this entity we're going to attempt to flip to someone else?" Worst case, the public benefit corp is converted to a non profit and tax deductible donations are used (potentially with a foundational fund built to operate in perpetuity, think Wikipedia) to fund the underlying storage and distribution infrastructure and labor costs for operations, similar to Signal and many other tech non profits.
https://www.youtube.com/watch?v=BzAdXyPYKQo (nsfw)
(Threads is always there for the normies until it enshittifies and Meta chases whatever catches Mark's eye next)