There stands no doubt that Angular has a higher learning curve than React. When you start learning React, you will find it easier initially, but it gets more challenging with more advanced functions adding up. To master the JS library, you will need to know the integration of new tools, which increases the complexity for developers.
On the other hand, Angular.js have complicated syntax to learn initially, but as you move to the advanced functions, you become familiar, making it easier to understand. It also gives additional powerful tools like dependency injection, which lures developers to use and learn it.