According to Vue.js' documentation, it is using a VDOM under the hood to render the UI. From my understanding, the VDOM was mainly invented in order to avoid "tracked dependencies". With a VDOM, it is possible to reconcile bigger parts of the application without knowing what exactly has changed. As a result, one can use plain objects and arrays to describe the view and just needs to inform the framework about a change (like setState in React). Then, both VDOM trees are compared and the minimal set of required changes is applied to the real DOM.
Vue.js, on the other hand, uses tracked dependencies. It knows exactly what has changed, so it would be possible to use DOM bindings. Furthermore, since most Vue.js users are already using the templating language, it doesn't really benefit from the greater flexibility provided by a VDOM. So why did Evan decide to use a VDOM?