This can be a bit weird if you’re used to building apps in an MVC kind of structure where everything needs to be separated or special functions and parsings are required to make it work. With React, you code with the end HTML output in mind — and react puts it all together for you. With Angular, you create your view and sort out your logic in your components.
HOC, context API, router components, view components, etc. I think there is plenty of opportunity in React as well for separation of concerns, and I would highly encourage it.