I feel as though I got burned a bit with AngularJS.
I went all out with it, learned it inside out, learned how to use Gulp, Bower, etc.
Then along comes Angular2 and it's completely different. Bower is deprecated, Gulp isn't widely used any more. It's all WebPack and Yarn.
I have spent some time with Angular2 and it is good. There's a lot to like, but it is exhausting having to learn everything I already know how to do in AngularJS again in a different framework, especially when I know I could just fire up AngularJS, get the old gang back together with Gulp/Bower etc and be done in a fraction of the time, because there's nothing new to learn.
So I've been learning Android development (in the context of Xamarin.Android) over the past year, and I am now at the point where I can do pretty much whatever I want to do in Android comfortably, and have shipped a couple of apps.
In the past month I've been learning Xamarin.iOS and it is starting to (slowly) click with me. I'm getting close to that know enough to be dangerous phase.
I feel as though these are better investments of my time. I am confident that Android and iOS will still be around in five years. Even if Xamarin isn't, Xamarin maps so closely to native development that if Microsoft gets bored of it, I could use Android Studio and XCode instead and still know what's going on.
I can't say the same for Angular, React, Vue, Webpack, Yarn, Aurelia, Ionic, etc etc. I have zero confidence that they will still be around in five years, and I don't want to learn any more client-side JS frameworks until the industry settles down and matures a bit.
If I need to build a single page app, AngularJS it is for the next year or two, because even if it isn't cool anymore, it's still fine.