"I never understood how JQuery and JS were just dumped the past 3-4 years in favor of all thse complex frameworks like AngularJS, Ember, etc..."
Well, you can't have Angular without JS so we'll focus on the point of jQuery here.
jQuery does a few things really well – so well that Angular itself uses jQuery (or jqLite by default). angular.element(selector) returns a jQuery object.
Angular also does a few things well. Code reusability and testability are much easier to achieve with Angular, in my opinion. Features like data-binding also help to reduce boilerplate code.
There was a similar discussion last week. What I said then was that a lot of the things you would use jQuery for have a different solution in Angular: https://news.ycombinator.com/item?id=7396016.
jQlite is a pretty small subset of jQuery. Many things are left out to keep it lean. For example $(el).offset()/height()/width() etc. Mostly only the DOM methods are left as they do still need a bit of normalization across browsers.
Well, you can't have Angular without JS so we'll focus on the point of jQuery here.
jQuery does a few things really well – so well that Angular itself uses jQuery (or jqLite by default). angular.element(selector) returns a jQuery object.
Angular also does a few things well. Code reusability and testability are much easier to achieve with Angular, in my opinion. Features like data-binding also help to reduce boilerplate code.