You're missing the point. You're talking about what you used for your project. I'm talking about learning skills so I can walk into an interview for a job that says "we need React developers". They may use any number of these things I mentioned, or are thinking about using them, and will bring them up. As a "React developer" I have to be aware of the ecosystem. So it's not just "learn an API with a few functions".
And, as I said, it matters not whether I learned these things on my own: to Get the Job you need to demonstrate real-world experience.
I strongly disagree with the idea that you need to know how to use react-saga or react-redux-router to walk into an interview that name drops React.
Like, it would be a huge plus from a candidate if they even knew the name GraphQL/Relay, but I wouldn't want to work somewhere that expected me to know it completely.
And, as I said, it matters not whether I learned these things on my own: to Get the Job you need to demonstrate real-world experience.