When you saw the new features listed on the official blog:
useTransition: Just startTransition with pending state.
useActionState: useTransition useState
Form action as function: VS react-hook-form
useFormStatus: useContext(
useOptimistic: HERE COMES A NEW CHALLENGER!
use: React.lazy without dynamic import @tanstack/query
Server component and Server Action: for SSR Only
ref as Prop: Yes. you can cleanup as callback ref. This feature has made other JS libraries more friendly, making it worth competing with other frontend tech stacks.
Hydration error: for SSR Only 2
Context is Provider by default: The beginning of the end for class components.