It is a complete waste of time and life to learn a different framework to solve the same problem (Both AngularJS and Angular build A+ UI's, but both require a lot of time to learn). It's dumb to spend 200 hours learning AngularJS, then 200 hours learning Angular when you could spend 200 hours learning AngularJS and 200 hours learning how to solve a different problem (like AI/ML, Data Science, AR/VR, Digital Marketing, etc.)