As someone who uses Vue every day at work I would not say that Vue has a simple API, though it has many conveniences.

I think a fair comparison would be to look at React's component API: https://facebook.github.io/react/docs/react-component.html

And compare it with the Options / Lifecycle Hooks and Instance Properties and Instance Methods sections of the Vue API docs: https://vuejs.org/v2/api/

Vue may be simpler if you have passing familiarity with Angular 1, or if you are very familiar with Mustache-style templates. But I think it's wrong to say the API is simple, or has a small surface.

The naming all life cycle methods, the grouping of things by categories in data, methods, all the things you don't need to learn to make jsx do what you want, the whole props/callback things that is vastly simpler, no set state shenanigan, no two ways with consequences of creating components, the use of standard html attribute names and not js dom api names, etc.

That makes manipulating the api way simpler for me.

> The api is simple, with no surprises

There are surprises. Reactivity with child components, and how to deal with that - there's enough "this isn't what I was expecting" that I run in to a lot in the forums that it's certainly a "surprise" to many.

> Vue doesn't force components or build tools on you.

Neither does React. Both components and JSX are optional, you can just build a vdom out of function calls.