React's original problem was that its users were expecting a framework and got a library. It's not semantics what matters here, but the fact it didn't take care

React's original problem was that its users were expecting a framework and got a library. It's not semantics what matters here, but the fact it didn't take care of fundamental parts of web apps, leaving those to be handled by someone else. And the result was often a buggy, half-working slow app, due to a mismatch of different modules. In my opinion, it is kind of like the "C" of web languages, in a way. It is powerful, but certain concepts are difficult to master and leave out too many important features. This is why nextJS is becoming so popular.