It is not real AngularJS problem but JavaScript problem. When JavaScript is built into a platform, it is always difficult to learn and to use at the very beginning. AngularJS is one of the two most popular JavaScript platforms for building front end of web apps. The other one is Sencha's ExtJS. They are platforms built on HTML5/CSS, the next generation web technology, and for modern apps which usually require to support multiple devices. They have big learning curve but when you learnt it, it is fine.
As to PHP5 and RoR, their time is gone. Looking at those job postings, how many are for the them. They are still used and might be better for some use cases but they are not for future.