How are they going to do that? The only way it’s conceivable is a hard fork, or something equivalent, or some very abrupt architectural and strategic changes that would seem just as disruptive to users (and much more disruptive to heavily invested partners).
I made the same prediction about hooks, but the fundamental difference is that you can ignore hooks. You can drop in basically any state/effect system and interop with components using their own, or hooks, or whatever. But you literally can’t even import existing components or call existing APIs (even hooks!) without rethinking the call stack. Parents and children are much more coupled than they used to be. Some libraries will either earnestly adopt RSC, or will make minimal necessary changes to be compatible, and propagate the problem to each of their consumers. And they, in turn, will have to choose whether to adapt to these factors within React… or without.
And again, as an observer, it doesn’t seem like that prospect is being received very well. It seems like it’s being received the same way Angular 2 was: you’re in for some large dose of pain no matter what you choose to do, and “no one ever gets fired for choosing ___” feels a lot less of a safe bet.
And unlike the Angular 2 experience, the other options are increasingly viable and mature and well received. My knowledge transfer to Solid took a few hours playing with a toy project for fun. Which is notably far less time and effort than I’d expect to spend getting up to speed with React today.
I’d be happy to be wrong, I actually want the React team to succeed on several different highly principled vectors. But at minimum I think they’re going to need to really rethink how they’re communicating this set of changes and very probably how they’re rolling them out.