Unfortunately, the general sense from the community is that it's an essential piece of the React ecosystem.
There's a reason why many experienced developers choose Redux to manage the state of their React apps. Specially once you get into async and server-side rendering, you will want or need Redux middleware such as Redux-Thunk-- or perhaps you'd like to take it a step further into observables with RxJS and Redux-Observable.
Perhaps these are all just a bunch of terms that you might not know that you need when you're first getting into React. But if you want performance and scalability -- and need an app that can withstand the pressures of today's demands -- then you may actually want to learn about all of these possibilities.
But sure -- if you're just getting into react, then by all means learn React on its own. But if you're running a large production app, I would recommend that you use redux and perhaps RxJS in conjunction with it.