Correct, React is essentially a tree diffing & reconciliation library tailored for the DOM. As such its foremost concern is to provide a declarative API for man

Correct, React is essentially a tree diffing & reconciliation library tailored for the DOM. As such its foremost concern is to provide a declarative API for manipulating the UI tree. How data flows into that tree is not its concern. This is why there's a wide variety of state management libraries available. Empirically I agree teams often get state management wrong, because it requires a different skillset than developing reusable UI components. Frameworks like Angular make a lot of hard choices outside the view layer for you.