There are several business reasons to do update, I'll take you through a few if them.
* We operate a lot of IT systems, some of them are build in corporation with smaller local firms. This isn't necessarily the most sound decision financially, but it's a political decision to support the local area. We handle the business end, the project management, we do fairly strict code reviews and we take over once it's ready for operations. I said it wasn't the most sound decision financially, but so far it's actually been a cheap way to develop smaller user friendly functionality in a lot of areas. None of these small companies have AngularJS qualified people anymore, and haven't had for a while.
* I can't hire people to do AngularJS. It didn't stick around for long enough for any real talent to develop on it, at least not in Denmark. I'm not hiring from the most lucrative position either, mind you, it's the public sector after all.
* I don't want to operate two Angular versions in my stack. I already manage more than 500 different IT systems, it'd be crazy to manage more JavaScript frameworks than I have to.
* I spend a lot more than $60k upgrading my employees. A few of my developers wanted to go with Angular 2 rather than stick with AngularJS. I'm perfectly fine with that. They could've learned something else, but I generally let my employees chose their direction as long as it also makes sense on the business end. This upgrade was perfectly fine with me.
Unless Google does a completely new take on Angular2-6 in the coming years, it'll turn out to save me a lot more than the $60k in the long run.