It's very well structured, easy to understand, batteries included, lends itself well to maintainability and scale.
When working for a company with staff below me who had very basic understanding of JS (having just done HTML/CSS/JQuery, had no idea what a promise was), there was almost no learning curve with Angular. The hardest part was understanding what a component was, then learning the folder structure.
Angular's seamless use of templating, the built in support for CSS pre-processing and simplicity of uni-directional databinding had the entire team pick it up and be productive almost immediately.
Using decorators to declare inputs/outputs on dumb components is clear, readable and easy to understand.
Class based components are also very clear.
Some say TS is annoying and all power to you, but using types is optional. Personally, TS has allowed me to save on some test cases by virtue of the compiler catching those issues. Plus there is a comfort in quality intellisense.
Vue is cool, it's like a less opinionated Angular. In my opinion, it's strength is its ability to be dropped into any project, giving you client side components and databinding irrespective of your stack. However I have experienced growing pains in larger projects as a result of people over complicating simple solutions.
I am still relatively inexperienced though, and I intend to spend more time with Vue to see if I can't like it more. I'm sure all of my concerns are addressable. So far though, Angular has treated me very kindly, both in large and small scale projects.