My previous job was on a product that used CoffeeScript and Backbone. As a stereotypical front end hipster, I was worried at first. I thought: "This is really old stuff in JS time. There are shiny new things out there". But I soon saw that while it would be more fun to use a new framework/language, the old ones are _totally fine_.
CoffeeScript was last updated a week ago. Backbone was updated several times last year and 1.4 is expected some time soon. There are online communities, there is documentation, there are answered questions on stackoverflow. Yeah, everything feels a bit old, but there won't be breaking changes to the API every few months and that blog post from 2015 that solves your exact problem is still useful!
Try looking at it like Angular is a language, not a framework. Sure, there are fancier ones coming out all the time, but that doesn't mean you have to switch every time that happens. The one you know has a bunch of apps built in it, you can still learn about its intricacies and there will be jobs for you for quite some time.