What most people want is an easy way to pass down state to nested components, but the context API is a bit verbose and otherwise you end up with the props-drilling problem, passing and passing and passing.
Problem is, Redux and MobX solve far more than this problem and in the end you are stuck with all the complexity they add, even if you don't need the other benefits they bring.
In 80% of all apps you don't need much state. They don't have deeply nested components so you can simply store the state in your root components (Screen/Page) via setState and pass everything down via props.
If you end up with deeply nested probs, use "unstated", it adds a bit better usability to the context API and lets you avoid the props-drilling problem. You basically get something like the "connect" from Redux, without the rest Redux would require.
If you somehow end up with an app that fits in the 1% who need fully predictable control over their global state, go for Redux.
React is the simplest framework I've ever seen, sadly Redux and co made it much more complex than needed to be, which drove many people away from it.